From: lei lu llfamsec@gmail.com
mainline inclusion from mainline-v6.10-rc2 commit fb63435b7c7dc112b1ae1baea5486e0a6e27b196 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAG8QA CVE: CVE-2024-41014
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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There is a lack of verification of the space occupied by fixed members of xlog_op_header in the xlog_recover_process_data.
We can create a crafted image to trigger an out of bounds read by following these steps: 1) Mount an image of xfs, and do some file operations to leave records 2) Before umounting, copy the image for subsequent steps to simulate abnormal exit. Because umount will ensure that tail_blk and head_blk are the same, which will result in the inability to enter xlog_recover_process_data 3) Write a tool to parse and modify the copied image in step 2 4) Make the end of the xlog_op_header entries only 1 byte away from xlog_rec_header->h_size 5) xlog_rec_header->h_num_logops++ 6) Modify xlog_rec_header->h_crc
Fix: Add a check to make sure there is sufficient space to access fixed members of xlog_op_header.
Signed-off-by: lei lu llfamsec@gmail.com Reviewed-by: Dave Chinner dchinner@redhat.com Reviewed-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Chandan Babu R chandanbabu@kernel.org Signed-off-by: Long Li leo.lilong@huawei.com --- fs/xfs/xfs_log_recover.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 898c65b77457..6b199fda9af2 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -2438,7 +2438,10 @@ xlog_recover_process_data(
ohead = (struct xlog_op_header *)dp; dp += sizeof(*ohead); - ASSERT(dp <= end); + if (dp > end) { + xfs_warn(log->l_mp, "%s: op header overrun", __func__); + return -EFSCORRUPTED; + }
/* errors will abort recovery */ error = xlog_recover_process_ophdr(log, rhash, rhead, ohead,