[PATCH 5.12 238/242] jfs: fix GPF in diFree

Greg Kroah-Hartman
2021-07-15T19:21:06Z

From: Pavel Skripkin <paskripkin@gmail.com>

commit 9d574f985fe33efd6911f4d752de6f485a1ea732 upstream.

Avoid passing inode with
JFS_SBI(inode->i_sb)->ipimap == NULL to
diFree()[1]. GFP will appear:

struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap;
struct inomap *imap = JFS_IP(ipimap)->i_imap;

JFS_IP() will return invalid pointer when ipimap == NULL

Call Trace:
diFree+0x13d/0x2dc0 fs/jfs/jfs_imap.c:853 [1]
jfs_evict_inode+0x2c9/0x370 fs/jfs/inode.c:154
evict+0x2ed/0x750 fs/inode.c:578
iput_final fs/inode.c:1654 [inline]
iput.part.0+0x3fe/0x820 fs/inode.c:1680
iput+0x58/0x70 fs/inode.c:1670

Reported-and-tested-by: syzbot+0a89a7b56db04c21a656@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/jfs/inode.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -151,7 +151,8 @@ void jfs_evict_inode(struct inode *inode
if (test_cflag(COMMIT_Freewmap, inode))
jfs_free_zero_link(inode);

- diFree(inode);
+ if (JFS_SBI(inode->i_sb)->ipimap)
+ diFree(inode);

/*
* Free the inode from the quota allocation.