mirror/glibc
2
0
Fork 0
mirror of git://sourceware.org/git/glibc.git synced 2025-03-31 14:01:18 +08:00
Code Issues Packages Projects Releases Wiki Activity

malloc: Avoid premature fallback to mmap [BZ #20284]

Browse Source 
Before this change, the while loop in reused_arena which avoids
returning a corrupt arena would never execute its body if the selected
arena were not corrupt.  As a result, result == begin after the loop,
and the function returns NULL, triggering fallback to mmap.
This commit is contained in:
Florian Weimer 2016-06-21 21:29:21 +02:00
parent 4751bbe2ad
commit a3b473373e
2 changed files with 10 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
ChangeLog
View File

@ -1,3 +1,9 @@
2016-06-21 Florian Weimer <fweimer@redhat.com>
[BZ #20284]
* malloc/arena.c (reused_arena): Do not return NULL if we start
out with a non-corrupted arena.
2016-06-21 Adhemerval Zanella <adhemerval.zanella@linaro.org>
* misc/Makefile (tests): Add tst-preadvwritev and tst-preadvwritev64.

10
malloc/arena.c
View File

@ -771,14 +771,12 @@ reused_arena (mstate avoid_arena)
{
result = result->next;
if (result == begin)
break;
/* We looped around the arena list. We could not find any
arena that was either not corrupted or not the one we
wanted to avoid. */
return NULL;
}
/* We could not find any arena that was either not corrupted or not the one
we wanted to avoid. */
if (result == begin || result == avoid_arena)
return NULL;
/* No arena available without contention. Wait for the next in line. */
LIBC_PROBE (memory_arena_reuse_wait, 3, &result->mutex, result, avoid_arena);
(void) mutex_lock (&result->mutex);