ext2: Check return value from ext2_get_group_desc()

ext2_get_group_desc() can return NULL if there is some error. This
usually means there is some programming error in the ext2 driver itself
but let's be defensive and handle that case.

Coverity-id: 115628
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c
index efe5fb21c533..04e73a99902b 100644
--- a/fs/ext2/ialloc.c
+++ b/fs/ext2/ialloc.c
@@ -465,6 +465,11 @@ struct inode *ext2_new_inode(struct inode *dir, umode_t mode,
 
         for (i = 0; i < sbi->s_groups_count; i++) {
                 gdp = ext2_get_group_desc(sb, group, &bh2);
+                if (!gdp) {
+                        if (++group == sbi->s_groups_count)
+                                group = 0;
+                        continue;
+                }
                 brelse(bitmap_bh);
                 bitmap_bh = read_inode_bitmap(sb, group);
                 if (!bitmap_bh) {