Second batch of backported fixes

getlogin/getlogin_r, zic

Signed-off-by: Alexey Neyman <stilor@att.net>
This commit is contained in:
Alexey Neyman 2018-05-12 23:17:03 -07:00
parent 387c8d8e2c
commit 2b055ddc67
51 changed files with 2584 additions and 0 deletions

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@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -393,6 +393,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

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@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

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@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1713,7 +1713,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

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@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -350,6 +350,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

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@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -83,7 +83,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -92,7 +92,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

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@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1648,7 +1648,7 @@
#define DO(field) (void) fwrite((void *) tzh.field, \
(size_t) sizeof tzh.field, (size_t) 1, fp)
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

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@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -350,6 +350,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

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@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -83,7 +83,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -92,7 +92,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

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@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1648,7 +1648,7 @@
#define DO(field) (void) fwrite((void *) tzh.field, \
(size_t) sizeof tzh.field, (size_t) 1, fp)
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -350,6 +350,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

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@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -83,7 +83,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -92,7 +92,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1648,7 +1648,7 @@
#define DO(field) (void) fwrite((void *) tzh.field, \
(size_t) sizeof tzh.field, (size_t) 1, fp)
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -350,6 +350,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -83,7 +83,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -92,7 +92,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1648,7 +1648,7 @@
#define DO(field) (void) fwrite((void *) tzh.field, \
(size_t) sizeof tzh.field, (size_t) 1, fp)
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -375,6 +375,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -61,10 +61,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -83,7 +83,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -92,7 +92,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1648,7 +1648,7 @@
#define DO(field) (void) fwrite((void *) tzh.field, \
(size_t) sizeof tzh.field, (size_t) 1, fp)
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -375,6 +375,15 @@
# define __glibc_unlikely(cond) (cond)
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -60,10 +60,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1695,7 +1695,7 @@
#define DO(field) (void) fwrite((void *) tzh.field, \
(size_t) sizeof tzh.field, (size_t) 1, fp)
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -382,6 +382,15 @@
# define __glibc_unlikely(cond) (cond)
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -60,10 +60,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1609,7 +1609,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -382,6 +382,15 @@
# define __glibc_likely(cond) (cond)
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1609,7 +1609,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = ZIC_VERSION;
convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -382,6 +382,15 @@
# define __glibc_likely(cond) (cond)
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1676,7 +1676,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -392,6 +392,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1713,7 +1713,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -399,6 +399,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#include <bits/wordsize.h>
#if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1713,7 +1713,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -399,6 +399,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#if (!defined _Static_assert && !defined __cplusplus \
&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
&& (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__))
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -82,7 +82,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -91,7 +91,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1713,7 +1713,7 @@
}
#define DO(field) ((void) fwrite(tzh.field, sizeof tzh.field, 1, fp))
tzh = tzh0;
- (void) strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -399,6 +399,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#if (!defined _Static_assert && !defined __cplusplus \
&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
&& (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__))
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -80,7 +80,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -89,7 +89,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1819,7 +1819,7 @@
}
#define DO(field) fwrite(tzh.field, sizeof tzh.field, 1, fp)
tzh = tzh0;
- strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -404,6 +404,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#if (!defined _Static_assert && !defined __cplusplus \
&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
&& (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__))
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -80,7 +80,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -89,7 +89,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1819,7 +1819,7 @@
}
#define DO(field) fwrite(tzh.field, sizeof tzh.field, 1, fp)
tzh = tzh0;
- strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -430,6 +430,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#if (!defined _Static_assert && !defined __cplusplus \
&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
&& (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__))
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -80,7 +80,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -89,7 +89,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1819,7 +1819,7 @@
}
#define DO(field) fwrite(tzh.field, sizeof tzh.field, 1, fp)
tzh = tzh0;
- strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);

View File

@ -0,0 +1,80 @@
commit 7532837d7b03b3ca5b9a63d77a5bd81dd23f3d9c
Author: Martin Sebor <msebor@redhat.com>
Date: Wed Nov 15 17:39:59 2017 -0700
The -Wstringop-truncation option new in GCC 8 detects common misuses
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
---
misc/sys/cdefs.h | 9 +++++++++
sysdeps/gnu/bits/utmp.h | 9 ++++++---
sysdeps/unix/sysv/linux/s390/bits/utmp.h | 9 ++++++---
3 files changed, 21 insertions(+), 6 deletions(-)
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -408,6 +408,15 @@
# endif
#endif
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+ argument to strncpy and strncat, as the char array is not necessarily
+ a NUL-terminated string. */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
#if (!defined _Static_assert && !defined __cplusplus \
&& (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
&& (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__))
--- a/sysdeps/gnu/bits/utmp.h
+++ b/sysdeps/gnu/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled
--- a/sysdeps/unix/sysv/linux/s390/bits/utmp.h
+++ b/sysdeps/unix/sysv/linux/s390/bits/utmp.h
@@ -59,10 +59,13 @@
{
short int ut_type; /* Type of login. */
pid_t ut_pid; /* Process ID of login process. */
- char ut_line[UT_LINESIZE]; /* Devicename. */
+ char ut_line[UT_LINESIZE]
+ __attribute_nonstring__; /* Devicename. */
char ut_id[4]; /* Inittab ID. */
- char ut_user[UT_NAMESIZE]; /* Username. */
- char ut_host[UT_HOSTSIZE]; /* Hostname for remote login. */
+ char ut_user[UT_NAMESIZE]
+ __attribute_nonstring__; /* Username. */
+ char ut_host[UT_HOSTSIZE]
+ __attribute_nonstring__; /* Hostname for remote login. */
struct exit_status ut_exit; /* Exit status of a process marked
as DEAD_PROCESS. */
/* The ut_session and ut_tv fields must be the same size when compiled

View File

@ -0,0 +1,47 @@
commit 4bae615022cb5a5da79ccda83cc6c9ba9f2d479c
Author: Joseph Myers <joseph@codesourcery.com>
Date: Wed Nov 22 18:44:23 2017 +0000
Avoid use of strlen in getlogin_r (bug 22447).
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
---
sysdeps/unix/getlogin_r.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/sysdeps/unix/getlogin_r.c
+++ b/sysdeps/unix/getlogin_r.c
@@ -80,7 +80,7 @@
if (result == 0)
{
- size_t needed = strlen (ut->ut_user) + 1;
+ size_t needed = __strnlen (ut->ut_user, UT_NAMESIZE) + 1;
if (needed > name_len)
{
@@ -89,7 +89,8 @@
}
else
{
- memcpy (name, ut->ut_user, needed);
+ memcpy (name, ut->ut_user, needed - 1);
+ name[needed - 1] = 0;
result = 0;
}
}

View File

@ -0,0 +1,25 @@
commit e69897bf202e18034cbef26f363bae64de70a196
Author: Paul Eggert <eggert@cs.ucla.edu>
Date: Sun Nov 12 22:00:28 2017 -0800
timezone: pacify GCC -Wstringop-truncation
Problem reported by Martin Sebor in:
https://sourceware.org/ml/libc-alpha/2017-11/msg00336.html
* timezone/zic.c (writezone): Use memcpy, not strncpy.
---
timezone/zic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/timezone/zic.c
+++ b/timezone/zic.c
@@ -1949,7 +1949,7 @@
}
#define DO(field) fwrite(tzh.field, sizeof tzh.field, 1, fp)
tzh = tzh0;
- strncpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
+ memcpy(tzh.tzh_magic, TZ_MAGIC, sizeof tzh.tzh_magic);
tzh.tzh_version[0] = version;
convert(thistypecnt, tzh.tzh_ttisgmtcnt);
convert(thistypecnt, tzh.tzh_ttisstdcnt);