ExternalVendorCode/genode
1
0
Fork 0
mirror of https://github.com/genodelabs/genode.git synced 2025-06-18 15:18:20 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Check for symlink target length errors

Browse Source 
Check for symlink length errors at the VFS library and the ram_fs and
vfs servers.

Fix #2462
This commit is contained in:
Emery Hemingway
2017-07-12 10:05:38 -05:00
committed by Christian Helmuth
parent cfdac3f4c3
commit 2deddf1e6d
5 changed files with 46 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
repos/os/src/lib/vfs/fs_file_system.h
View File

@ -530,6 +530,8 @@ class Vfs::Fs_file_system : public File_system
Symlink_result symlink(char const *from, char const *to) override
{
auto const from_len = strlen(from);
/*
* We write to the symlink via the packet stream. Hence we need
* to serialize with other packet-stream operations.
@ -550,10 +552,18 @@ class Vfs::Fs_file_system : public File_system
Fs_handle_guard from_dir_guard(*this, _fs, dir_handle, _handle_space);
::File_system::Symlink_handle symlink_handle =
_fs.symlink(dir_handle, symlink_name.base() + 1, true);
_fs.symlink(dir_handle, symlink_name.base() + 1, true);
Fs_handle_guard symlink_guard(*this, _fs, symlink_handle, _handle_space);
_write(symlink_guard, from, strlen(from) + 1, 0);
auto const n = _write(symlink_guard, from, from_len, 0);
/*
* a convention at the VFS server is to return an invalid
* result length when the target is too long
*/
if (n != from_len) {
return n ? SYMLINK_ERR_NAME_TOO_LONG : SYMLINK_ERR_NO_PERM;
}
}
catch (::File_system::Invalid_handle) { return SYMLINK_ERR_NO_ENTRY; }
catch (::File_system::Node_already_exists) { return SYMLINK_ERR_EXISTS; }