From 9835632cf43fd6d1f8b8f40a88892a45b6bfad6e Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 29 Dec 2020 17:12:21 -0300 Subject: malloc: preserve errno on mcheck hooks [BZ #17924] Similar to the fix 69fda43b8d, save and restore errno for the hook functions used for MALLOC_CHECK_=3. It fixes the malloc/tst-free-errno-mcheck regression. Checked on x86_64-linux-gnu. --- malloc/hooks.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'malloc') diff --git a/malloc/hooks.c b/malloc/hooks.c index 6474ba8..fc285f1 100644 --- a/malloc/hooks.c +++ b/malloc/hooks.c @@ -260,6 +260,8 @@ free_check (void *mem, const void *caller) if (!mem) return; + int err = errno; + #ifdef USE_MTAG /* Quickly check that the freed pointer matches the tag for the memory. This gives a useful double-free detection. */ @@ -274,12 +276,16 @@ free_check (void *mem, const void *caller) { __libc_lock_unlock (main_arena.mutex); munmap_chunk (p); - return; } - /* Mark the chunk as belonging to the library again. */ - (void)TAG_REGION (chunk2rawmem (p), CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ); - _int_free (&main_arena, p, 1); - __libc_lock_unlock (main_arena.mutex); + else + { + /* Mark the chunk as belonging to the library again. */ + (void)TAG_REGION (chunk2rawmem (p), CHUNK_AVAILABLE_SIZE (p) + - CHUNK_HDR_SZ); + _int_free (&main_arena, p, 1); + __libc_lock_unlock (main_arena.mutex); + } + __set_errno (err); } static void * -- cgit v1.1