mirror of
https://github.com/crosstool-ng/crosstool-ng.git
synced 2024-12-21 13:47:48 +00:00
86c2982568
This refreshes the line numbers, removes any fuzz (which would make any future forward ports easier) and standardizes the patch/file headers (which makes them easier to read). Signed-off-by: Alexey Neyman <stilor@att.net>
71 lines
2.0 KiB
Diff
71 lines
2.0 KiB
Diff
From 9df2d784439720abbf67fa96c6515a5c4a9f230a Mon Sep 17 00:00:00 2001
|
|
From: Keith Packard <keithp@keithp.com>
|
|
Date: Thu, 14 Jan 2021 18:48:44 -0800
|
|
Subject: [PATCH 2/2] tinystdio: Fix snprintf(buf, 0, ...) to not smash buffer
|
|
|
|
snprintf(buf, 0) should not write anything to the destination, not
|
|
even a trailing '\0'. The tinystdio implementation had a signed
|
|
comparison bug where this case would cause a null to be placed in the
|
|
output buffer at the size of the data that would have been written.
|
|
|
|
Add a test to make sure snprintf respects the 'len' parameter
|
|
correctly.
|
|
|
|
Signed-off-by: Keith Packard <keithp@keithp.com>
|
|
---
|
|
newlib/libc/tinystdio/snprintf.c | 2 +-
|
|
test/printf_scanf.c | 31 +++++++++++++++++++++++++++++++
|
|
2 files changed, 32 insertions(+), 1 deletion(-)
|
|
|
|
--- a/newlib/libc/tinystdio/snprintf.c
|
|
+++ b/newlib/libc/tinystdio/snprintf.c
|
|
@@ -56,7 +56,7 @@
|
|
i = vfprintf(&f.file, fmt, ap);
|
|
va_end(ap);
|
|
|
|
- if (n >= 0 && i >= 0)
|
|
+ if ((int) n >= 0 && i >= 0)
|
|
s[i < n ? i : n] = 0;
|
|
|
|
return i;
|
|
--- a/test/printf_scanf.c
|
|
+++ b/test/printf_scanf.c
|
|
@@ -96,6 +96,37 @@
|
|
fflush(stdout);
|
|
}
|
|
#endif
|
|
+
|
|
+ /*
|
|
+ * test snprintf to make sure it doesn't overwrite the specified buffer
|
|
+ * length (even if that is zero)
|
|
+ */
|
|
+ for (x = 0; x <= 6; x++) {
|
|
+ char tbuf[10] = "xxxxxxxxx";
|
|
+ const char ref[10] = "xxxxxxxxx";
|
|
+ int i = snprintf(tbuf, x, "%s", "123");
|
|
+ int y = x <= 4 ? x : 4;
|
|
+ if (i != 3) {
|
|
+ printf("snprintf(tbuf, %d, \"%%s\", \"123\") return %d instead of %d\n",
|
|
+ x, i, 3);
|
|
+ errors++;
|
|
+ }
|
|
+ int l = strlen(tbuf);
|
|
+ if (y > 0 && l != y - 1) {
|
|
+ printf("returned buffer len want %d got %d\n", y - 1, l);
|
|
+ errors++;
|
|
+ }
|
|
+ if (y > 0 && strncmp(tbuf, "123", y - 1) != 0) {
|
|
+ strncpy(buf, "123", y - 1);
|
|
+ buf[y-1] = '\0';
|
|
+ printf("returned buffer want %s got %s\n", buf, tbuf);
|
|
+ errors++;
|
|
+ }
|
|
+ if (memcmp(tbuf + y, ref + y, sizeof(tbuf) - y) != 0) {
|
|
+ printf("tail of buf mangled %s\n", tbuf + y);
|
|
+ errors++;
|
|
+ }
|
|
+ }
|
|
for (x = 0; x < 32; x++) {
|
|
unsigned int v = 0x12345678 >> x;
|
|
unsigned int r;
|