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author | Zixuan Fu <r33s3n6@gmail.com> | 2022-04-11 13:45:34 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-09 11:20:57 +0300 |
commit | 9dfa8d087bb854f613fcdbf1af4fb02c0b2d1e4f (patch) | |
tree | d02eebf943327c91229e8744b5e460e75167c3de /fs/jfs | |
parent | 05efc4591f80582b6fe53366b70b6a35a42fd255 (diff) | |
download | linux-9dfa8d087bb854f613fcdbf1af4fb02c0b2d1e4f.tar.xz |
fs: jfs: fix possible NULL pointer dereference in dbFree()
[ Upstream commit 0d4837fdb796f99369cf7691d33de1b856bcaf1f ]
In our fault-injection testing, the variable "nblocks" in dbFree() can be
zero when kmalloc_array() fails in dtSearch(). In this case, the variable
"mp" in dbFree() would be NULL and then it is dereferenced in
"write_metapage(mp)".
The failure log is listed as follows:
[ 13.824137] BUG: kernel NULL pointer dereference, address: 0000000000000020
...
[ 13.827416] RIP: 0010:dbFree+0x5f7/0x910 [jfs]
[ 13.834341] Call Trace:
[ 13.834540] <TASK>
[ 13.834713] txFreeMap+0x7b4/0xb10 [jfs]
[ 13.835038] txUpdateMap+0x311/0x650 [jfs]
[ 13.835375] jfs_lazycommit+0x5f2/0xc70 [jfs]
[ 13.835726] ? sched_dynamic_update+0x1b0/0x1b0
[ 13.836092] kthread+0x3c2/0x4a0
[ 13.836355] ? txLockFree+0x160/0x160 [jfs]
[ 13.836763] ? kthread_unuse_mm+0x160/0x160
[ 13.837106] ret_from_fork+0x1f/0x30
[ 13.837402] </TASK>
...
This patch adds a NULL check of "mp" before "write_metapage(mp)" is called.
Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Zixuan Fu <r33s3n6@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs/jfs')
-rw-r--r-- | fs/jfs/jfs_dmap.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c index e58ae29a223d..0ce17ea8fa8a 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -385,7 +385,8 @@ int dbFree(struct inode *ip, s64 blkno, s64 nblocks) } /* write the last buffer. */ - write_metapage(mp); + if (mp) + write_metapage(mp); IREAD_UNLOCK(ipbmap); |