From cb76994a1035d620176463560037f144232258d7 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Mon, 3 Sep 2012 17:12:29 +0300 Subject: [PATCH] UBI: fix a horrible memory deallocation bug UBI was mistakingly using 'kfree()' instead of 'kmem_cache_free()' when freeing "attach eraseblock" structures in vtbl.c. Thankfully, this happened only when we were doing auto-format, so many systems were unaffected. However, there are still many users affected. It is strange, but the system did not crash and nothing bad happened when the SLUB memory allocator was used. However, in case of SLOB we observed an crash right away. This problem was introduced in 2.6.39 by commit "4400ede UBI: add slab cache for ubi_scan_leb objects" A note for stable trees: Because variable were renamed, this won't cleanly apply to older kernels. Changing names like this should help: 1. ai -> si 2. aeb_slab_cache -> seb_slab_cache 3. new_aeb -> new_seb Reported-by: Richard Genoud Tested-by: Richard Genoud Tested-by: Artem Bityutskiy Cc: stable@vger.kernel.org [v2.6.39+] Signed-off-by: Artem Bityutskiy --- drivers/mtd/ubi/vtbl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/ubi/vtbl.c b/drivers/mtd/ubi/vtbl.c index 437bc193e170d..568307cc7caf8 100644 --- a/drivers/mtd/ubi/vtbl.c +++ b/drivers/mtd/ubi/vtbl.c @@ -340,7 +340,7 @@ retry: * of this LEB as it will be deleted and freed in 'ubi_add_to_av()'. */ err = ubi_add_to_av(ubi, ai, new_aeb->pnum, new_aeb->ec, vid_hdr, 0); - kfree(new_aeb); + kmem_cache_free(ai->aeb_slab_cache, new_aeb); ubi_free_vid_hdr(ubi, vid_hdr); return err; @@ -353,7 +353,7 @@ write_error: list_add(&new_aeb->u.list, &ai->erase); goto retry; } - kfree(new_aeb); + kmem_cache_free(ai->aeb_slab_cache, new_aeb); out_free: ubi_free_vid_hdr(ubi, vid_hdr); return err; -- 2.39.5