Re: [PATCH] string.h: un-fortify memcpy_and_pad
From: Martin Wilck <hidden>
Date: 2017-09-11 09:44:43
Also in:
linux-nvme, lkml
On Wed, 2017-09-06 at 14:36 +0200, Martin Wilck wrote:
The way I'd implemented the new helper memcpy_and_pad with __FORTIFY_INLINE caused compiler warnings for certain kernel configurations. This helper is only used in a single place at this time, and thus doesn't benefit much from fortification. So simplify the code by dropping fortification support for now. Fixes: 01f33c336e2d "string.h: add memcpy_and_pad()" Signed-off-by: Martin Wilck <redacted> Acked-by: Arnd Bergmann <arnd@arndb.de> --- include/linux/string.h | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-)
Hello Stephen and Christoph, my broken patch 01f33c336e2d is in Linus' tree and causing compiler warnings there. Could you please take care that this fix is pulled in on top of it? Or should I take another action myself? Thanks, Martin
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diff --git a/include/linux/string.h b/include/linux/string.h index e1eeb0a8a9693..54d21783e18dd 100644 --- a/include/linux/string.h +++ b/include/linux/string.h@@ -434,20 +434,9 @@ __FORTIFY_INLINE char *strcpy(char *p, constchar *q) * @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) +static 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);