ext4: fix potential null pointer dereference in ext4_free_inode
Fix potential null pointer dereferencing problem caused by e43bb4e612
("ext4: decrement free clusters/inodes counters when block group declared bad")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 0840bf3..5b87fc3 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -338,7 +338,7 @@
fatal = err;
} else {
ext4_error(sb, "bit already cleared for inode %lu", ino);
- if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
+ if (gdp && !EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
int count;
count = ext4_free_inodes_count(sb, gdp);
percpu_counter_sub(&sbi->s_freeinodes_counter,