[PATCH] xfs: check the return value of krealloc() in xfs_uuid_mount

[Qinglang Miao]

krealloc() may fail to expand the memory space. Add sanity checks to it,
and WARN() if that really happened.

Fixes: 771915c4f688 ("xfs: remove kmem_realloc()")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
---
 fs/xfs/xfs_mount.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 150ee5cb8..c07f48c32 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -80,9 +80,13 @@ xfs_uuid_mount(
 	}
 
 	if (hole < 0) {
-		xfs_uuid_table = krealloc(xfs_uuid_table,
+		uuid_t *if_xfs_uuid_table;
+		if_xfs_uuid_table = krealloc(xfs_uuid_table,
 			(xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
 			GFP_KERNEL | __GFP_NOFAIL);
+		if (!if_xfs_uuid_table)
+			goto out_duplicate;
+		xfs_uuid_table = if_xfs_uuid_table;
 		hole = xfs_uuid_table_size++;
 	}
 	xfs_uuid_table[hole] = *uuid;
-- 
2.23.0