Jann Horn ae119b7e12 mm: slub: add missing TID bump in kmem_cache_alloc_bulk()
commit fd4d9c7d0c71866ec0c2825189ebd2ce35bd95b8 upstream.

When kmem_cache_alloc_bulk() attempts to allocate N objects from a percpu
freelist of length M, and N > M > 0, it will first remove the M elements
from the percpu freelist, then call ___slab_alloc() to allocate the next
element and repopulate the percpu freelist. ___slab_alloc() can re-enable
IRQs via allocate_slab(), so the TID must be bumped before ___slab_alloc()
to properly commit the freelist head change.

Fix it by unconditionally bumping c->tid when entering the slowpath.

Cc: stable@vger.kernel.org
Fixes: ebe909e0fdb3 ("slub: improve bulk alloc strategy")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-21 08:11:58 +01:00
..
2019-09-24 15:54:08 -07:00
2019-08-30 22:43:58 -07:00
2019-09-24 15:54:08 -07:00
2018-06-07 17:34:36 -07:00
2019-09-24 15:54:08 -07:00
2019-09-04 13:40:49 -07:00
2019-09-25 17:51:41 -07:00
2019-09-17 15:20:17 -07:00
2019-09-24 15:54:12 -07:00