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| author | Martin Wilck <mwilck@suse.com> | 2017-08-14 22:12:38 +0200 |
|---|---|---|
| committer | Alexander Grund <flamefire89@gmail.com> | 2024-03-07 18:16:35 +0100 |
| commit | 02205a347c40cfbcc5ce34e4ecd63ea821221237 (patch) | |
| tree | 54bacd8a6ecec295837c5babad40c58195fa74b9 | |
| parent | 730045698af7aca1b622d9147d6ac66eb615c2ee (diff) | |
BACKPORT: string.h: add memcpy_and_pad()
commit 01f33c336e2d298ea5d4ce5d6e5bcd12865cc30f upstream.
This helper function is useful for the nvme subsystem, and maybe
others.
Note: the warnings reported by the kbuild test robot for this patch
are actually generated by the use of CONFIG_PROFILE_ALL_BRANCHES
together with __FORTIFY_INLINE.
Change-Id: I5f7e1e9143ce9df88af0afd02aef971d5172bd3e
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimbeg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[AG: Backported to 4.4]
Signed-off-by: Alexander Grund <theflamefire89@gmail.com>
| -rw-r--r-- | include/linux/string.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/include/linux/string.h b/include/linux/string.h index 1a9589a5ace6..84af888924e1 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -204,4 +204,33 @@ static inline const char *kbasename(const char *path) return tail ? tail + 1 : path; } +/** + * memcpy_and_pad - Copy one buffer to another with padding + * @dest: Where to copy to + * @dest_len: The destination buffer size + * @src: Where to copy from + * @count: The number of bytes to copy + * @pad: Character to use for padding if space is left in destination. + */ +__FORTIFY_INLINE void memcpy_and_pad(void *dest, size_t dest_len, + const void *src, size_t count, int pad) +{ + size_t dest_size = __builtin_object_size(dest, 0); + size_t src_size = __builtin_object_size(src, 0); + + if (__builtin_constant_p(dest_len) && __builtin_constant_p(count)) { + if (dest_size < dest_len && dest_size < count) + __write_overflow(); + else if (src_size < dest_len && src_size < count) + __read_overflow3(); + } + if (dest_size < dest_len) + fortify_panic(__func__); + if (dest_len > count) { + memcpy(dest, src, count); + memset(dest + count, pad, dest_len - count); + } else + memcpy(dest, src, dest_len); +} + #endif /* _LINUX_STRING_H_ */ |