Commit e7701557 authored Aug 02, 2017 by Arnd Bergmann Committed by Linus Torvalds Aug 02, 2017

kasan: avoid -Wmaybe-uninitialized warning

gcc-7 produces this warning:

  mm/kasan/report.c: In function 'kasan_report':
  mm/kasan/report.c:351:3: error: 'info.first_bad_addr' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     print_shadow_for_address(info->first_bad_addr);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  mm/kasan/report.c:360:27: note: 'info.first_bad_addr' was declared here

The code seems fine as we only print info.first_bad_addr when there is a
shadow, and we always initialize it in that case, but this is relatively
hard for gcc to figure out after the latest rework.

Adding an intialization to the most likely value together with the other
struct members shuts up that warning.

Fixes: b235b9808664 ("kasan: unify report headers")
Link: https://patchwork.kernel.org/patch/9641417/
Link: http://lkml.kernel.org/r/20170725152739.4176967-1-arnd@arndb.de


Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Alexander Potapenko <glider@google.com>
Suggested-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b2282371

mm/kasan/report.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -401,6 +401,7 @@ void kasan_report(unsigned long addr, size_t size,
		disable_trace_on_warning();

		info.access_addr = (void *)addr;
		info.first_bad_addr = (void *)addr;
		info.access_size = size;
		info.is_write = is_write;
		info.ip = ip;

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