diff options
| author | Edward Adam Davis <eadavis@qq.com> | 2024-04-11 20:05:28 +0800 |
|---|---|---|
| committer | Dave Kleikamp <dave.kleikamp@oracle.com> | 2024-06-26 12:27:33 -0500 |
| commit | ce6dede912f064a855acf6f04a04cbb2c25b8c8c (patch) | |
| tree | a0cbdffb4d8447ebfcf5a3e4b48874e926983f0d /fs/jfs | |
| parent | ee6817e72d4e690b65ce0f77f406ed1a1ac5b5c2 (diff) | |
jfs: fix null ptr deref in dtInsertEntry
[syzbot reported]
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 5061 Comm: syz-executor404 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:dtInsertEntry+0xd0c/0x1780 fs/jfs/jfs_dtree.c:3713
...
[Analyze]
In dtInsertEntry(), when the pointer h has the same value as p, after writing
name in UniStrncpy_to_le(), p->header.flag will be cleared. This will cause the
previously true judgment "p->header.flag & BT-LEAF" to change to no after writing
the name operation, this leads to entering an incorrect branch and accessing the
uninitialized object ih when judging this condition for the second time.
[Fix]
After got the page, check freelist first, if freelist == 0 then exit dtInsert()
and return -EINVAL.
Reported-by: syzbot+bba84aef3a26fb93deb9@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Diffstat (limited to 'fs/jfs')
| -rw-r--r-- | fs/jfs/jfs_dtree.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/jfs/jfs_dtree.c b/fs/jfs/jfs_dtree.c index 031d8f570f58..5d3127ca68a4 100644 --- a/fs/jfs/jfs_dtree.c +++ b/fs/jfs/jfs_dtree.c @@ -834,6 +834,8 @@ int dtInsert(tid_t tid, struct inode *ip, * the full page. */ DT_GETSEARCH(ip, btstack->top, bn, mp, p, index); + if (p->header.freelist == 0) + return -EINVAL; /* * insert entry for new key |