aboutsummaryrefslogtreecommitdiffstats
path: root/lib
diff options
context:
space:
mode:
authorRoland Dreier <roland@purestorage.com>2012-06-07 14:21:13 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-06-17 11:23:10 -0700
commit29684ecb7a675061933fb19531407fa9f9971ab4 (patch)
treeaa0b624b9a3862145503c2163802889f1ccf2eb0 /lib
parent3fbec23f6bc97f3721c5345659fbbb71542120c5 (diff)
downloadkernel_samsung_smdk4412-29684ecb7a675061933fb19531407fa9f9971ab4.zip
kernel_samsung_smdk4412-29684ecb7a675061933fb19531407fa9f9971ab4.tar.gz
kernel_samsung_smdk4412-29684ecb7a675061933fb19531407fa9f9971ab4.tar.bz2
btree: fix tree corruption in btree_get_prev()
commit cbf8ae32f66a9ceb8907ad9e16663c2a29e48990 upstream. The memory the parameter __key points to is used as an iterator in btree_get_prev(), so if we save off a bkey() pointer in retry_key and then assign that to __key, we'll end up corrupting the btree internals when we do eg longcpy(__key, bkey(geo, node, i), geo->keylen); to return the key value. What we should do instead is use longcpy() to copy the key value that retry_key points to __key. This can cause a btree to get corrupted by seemingly read-only operations such as btree_for_each_safe. [akpm@linux-foundation.org: avoid the double longcpy()] Signed-off-by: Roland Dreier <roland@purestorage.com> Acked-by: Joern Engel <joern@logfs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/btree.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/lib/btree.c b/lib/btree.c
index 2a34392..297124d 100644
--- a/lib/btree.c
+++ b/lib/btree.c
@@ -319,8 +319,8 @@ void *btree_get_prev(struct btree_head *head, struct btree_geo *geo,
if (head->height == 0)
return NULL;
-retry:
longcpy(key, __key, geo->keylen);
+retry:
dec_key(geo, key);
node = head->node;
@@ -351,7 +351,7 @@ retry:
}
miss:
if (retry_key) {
- __key = retry_key;
+ longcpy(key, retry_key, geo->keylen);
retry_key = NULL;
goto retry;
}