From: Yousef Alhouseen Date: Tue, 30 Jun 2026 10:06:07 +0000 (+0200) Subject: xfs: use null daddr for unset first bad log block X-Git-Tag: v7.2-rc2~15^2~4 X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=cc9af5e461ea5f6e37738f3f1e41c45a9b7f45d6;p=thirdparty%2Flinux.git xfs: use null daddr for unset first bad log block xlog_do_recovery_pass() may return before setting first_bad. The caller must distinguish that case from an error at a valid log block, including block zero after the log wraps. Initialize first_bad to XFS_BUF_DADDR_NULL and test it explicitly before treating the error as a torn write. Fixes: 7088c4136fa1 ("xfs: detect and trim torn writes during log recovery") Suggested-by: Darrick J. Wong Reported-by: syzbot+b7dfbed0c6c2b5e9fd34@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=b7dfbed0c6c2b5e9fd34 Cc: stable@vger.kernel.org # v4.5 Signed-off-by: Yousef Alhouseen Reviewed-by: "Darrick J. Wong" Signed-off-by: Carlos Maiolino --- diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 09e6678ca487..5f984bf5698a 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -1028,7 +1028,7 @@ xlog_verify_head( { struct xlog_rec_header *tmp_rhead; char *tmp_buffer; - xfs_daddr_t first_bad; + xfs_daddr_t first_bad = XFS_BUF_DADDR_NULL; xfs_daddr_t tmp_rhead_blk; int found; int error; @@ -1057,7 +1057,8 @@ xlog_verify_head( */ error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk, XLOG_RECOVER_CRCPASS, &first_bad); - if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) { + if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && + first_bad != XFS_BUF_DADDR_NULL) { /* * We've hit a potential torn write. Reset the error and warn * about it. @@ -3575,4 +3576,3 @@ xlog_recover_cancel( if (xlog_recovery_needed(log)) xlog_recover_cancel_intents(log); } -