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| author | Chao Yu <chao@kernel.org> | 2022-09-14 14:51:51 +0300 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2022-10-04 23:31:43 +0300 |
| commit | c6ad7fd16657ebd34a87a97d9588195aae87597d (patch) | |
| tree | 0958700e5e66aa02b06af47425e0f3f7402043f1 /fs/f2fs/recovery.c | |
| parent | 1e8a9191ccc286bbbfc1f9dccd31ac3bc9ec8a3f (diff) | |
| download | linux-c6ad7fd16657ebd34a87a97d9588195aae87597d.tar.xz | |
f2fs: fix to do sanity check on summary info
As Wenqing Liu reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=216456
BUG: KASAN: use-after-free in recover_data+0x63ae/0x6ae0 [f2fs]
Read of size 4 at addr ffff8881464dcd80 by task mount/1013
CPU: 3 PID: 1013 Comm: mount Tainted: G W 6.0.0-rc4 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
Call Trace:
dump_stack_lvl+0x45/0x5e
print_report.cold+0xf3/0x68d
kasan_report+0xa8/0x130
recover_data+0x63ae/0x6ae0 [f2fs]
f2fs_recover_fsync_data+0x120d/0x1fc0 [f2fs]
f2fs_fill_super+0x4665/0x61e0 [f2fs]
mount_bdev+0x2cf/0x3b0
legacy_get_tree+0xed/0x1d0
vfs_get_tree+0x81/0x2b0
path_mount+0x47e/0x19d0
do_mount+0xce/0xf0
__x64_sys_mount+0x12c/0x1a0
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The root cause is: in fuzzed image, SSA table is corrupted: ofs_in_node
is larger than ADDRS_PER_PAGE(), result in out-of-range access on 4k-size
page.
- recover_data
- do_recover_data
- check_index_in_prev_nodes
- f2fs_data_blkaddr
This patch adds sanity check on summary info in recovery and GC flow
in where the flows rely on them.
After patch:
[ 29.310883] F2FS-fs (loop0): Inconsistent ofs_in_node:65286 in summary, ino:0, nid:6, max:1018
Cc: stable@vger.kernel.org
Reported-by: Wenqing Liu <wenqingliu0120@gmail.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/recovery.c')
| -rw-r--r-- | fs/f2fs/recovery.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index 8326003e6918..5c9facec98f6 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -474,7 +474,7 @@ static int check_index_in_prev_nodes(struct f2fs_sb_info *sbi, struct dnode_of_data tdn = *dn; nid_t ino, nid; struct inode *inode; - unsigned int offset; + unsigned int offset, ofs_in_node, max_addrs; block_t bidx; int i; @@ -501,15 +501,24 @@ static int check_index_in_prev_nodes(struct f2fs_sb_info *sbi, got_it: /* Use the locked dnode page and inode */ nid = le32_to_cpu(sum.nid); + ofs_in_node = le16_to_cpu(sum.ofs_in_node); + + max_addrs = ADDRS_PER_PAGE(dn->node_page, dn->inode); + if (ofs_in_node >= max_addrs) { + f2fs_err(sbi, "Inconsistent ofs_in_node:%u in summary, ino:%lu, nid:%u, max:%u", + ofs_in_node, dn->inode->i_ino, nid, max_addrs); + return -EFSCORRUPTED; + } + if (dn->inode->i_ino == nid) { tdn.nid = nid; if (!dn->inode_page_locked) lock_page(dn->inode_page); tdn.node_page = dn->inode_page; - tdn.ofs_in_node = le16_to_cpu(sum.ofs_in_node); + tdn.ofs_in_node = ofs_in_node; goto truncate_out; } else if (dn->nid == nid) { - tdn.ofs_in_node = le16_to_cpu(sum.ofs_in_node); + tdn.ofs_in_node = ofs_in_node; goto truncate_out; } |