ocfs2: fix null pointer dereference in ocfs2_dir_foreach_blk_id()
Fix a NULL pointer deference while removing an empty directory, which
was introduced by commit 3704412bdbf3 ("[readdir] convert ocfs2").
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<(null)>] (null)
PGD 6da85067 PUD 6da89067 PMD 0
Oops: 0010 [#1] SMP
CPU: 0 PID: 6564 Comm: rmdir Tainted: G O 3.11.0-rc1 #4
RIP: 0010:[<0000000000000000>] [< (null)>] (null)
Call Trace:
ocfs2_dir_foreach+0x49/0x50 [ocfs2]
ocfs2_empty_dir+0x12c/0x3e0 [ocfs2]
ocfs2_unlink+0x56e/0xc10 [ocfs2]
vfs_rmdir+0xd5/0x140
do_rmdir+0x1cb/0x1e0
SyS_rmdir+0x16/0x20
system_call_fastpath+0x16/0x1b
Code: Bad RIP value.
RIP [< (null)>] (null)
RSP <ffff88006daddc10>
CR2: 0000000000000000
[dan.carpenter@oracle.com: fix pointer math]
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reported-by: David Weber <wb@munzinger.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index eb760d8..30544ce 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -2153,11 +2153,9 @@
{
int ret;
struct ocfs2_empty_dir_priv priv = {
- .ctx.actor = ocfs2_empty_dir_filldir
+ .ctx.actor = ocfs2_empty_dir_filldir,
};
- memset(&priv, 0, sizeof(priv));
-
if (ocfs2_dir_indexed(inode)) {
ret = ocfs2_empty_dir_dx(inode, &priv);
if (ret)