Merge branch 'guilt/xfs-5.19-recovery-buf-cancel' into xfs-5.19-for-next

As part of solving the memory leaks and UAF problems in the new LARP
code, kmemleak also reported that log recovery will leak the table
used to hash buffer cancellations if the recovery fails.  Fix this
problem by creating alloc/free helpers that initialize and free the
hashtable contents correctly.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 11 insertions, 23 deletions

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index b1980d7cbbee..5f7e4e6e33ce 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -3223,7 +3223,7 @@ xlog_do_log_recovery(
 	xfs_daddr_t	head_blk,
 	xfs_daddr_t	tail_blk)
 {
-	int		error, i;
+	int		error;
 
 	ASSERT(head_blk != tail_blk);
 
@@ -3231,37 +3231,25 @@ xlog_do_log_recovery(
 	 * First do a pass to find all of the cancelled buf log items.
 	 * Store them in the buf_cancel_table for use in the second pass.
 	 */
-	log->l_buf_cancel_table = kmem_zalloc(XLOG_BC_TABLE_SIZE *
-						 sizeof(struct list_head),
-						 0);
-	for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
-		INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
+	error = xlog_alloc_buf_cancel_table(log);
+	if (error)
+		return error;
 
 	error = xlog_do_recovery_pass(log, head_blk, tail_blk,
 				      XLOG_RECOVER_PASS1, NULL);
-	if (error != 0) {
-		kmem_free(log->l_buf_cancel_table);
-		log->l_buf_cancel_table = NULL;
-		return error;
-	}
+	if (error != 0)
+		goto out_cancel;
+
 	/*
 	 * Then do a second pass to actually recover the items in the log.
 	 * When it is complete free the table of buf cancel items.
 	 */
 	error = xlog_do_recovery_pass(log, head_blk, tail_blk,
 				      XLOG_RECOVER_PASS2, NULL);
-#ifdef DEBUG
-	if (!error) {
-		int	i;
-
-		for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
-			ASSERT(list_empty(&log->l_buf_cancel_table[i]));
-	}
-#endif	/* DEBUG */
-
-	kmem_free(log->l_buf_cancel_table);
-	log->l_buf_cancel_table = NULL;
-
+	if (!error)
+		xlog_check_buf_cancel_table(log);
+out_cancel:
+	xlog_free_buf_cancel_table(log);
 	return error;
 }