ext4: initialize err_blk before calling __ext4_get_inode_loc

It is not guaranteed that __ext4_get_inode_loc will definitely set
err_blk pointer when it returns EIO. To avoid using uninitialized
variables, let's first set err_blk to 0.

Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Harshad Shirwadkar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
Cc: [email protected]

Author: harshadjs

fs/ext4/inode.c

@@ -4524,7 +4524,7 @@ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino,
 static int __ext4_get_inode_loc_noinmem(struct inode *inode,
 					struct ext4_iloc *iloc)
 {
-	ext4_fsblk_t err_blk;
+	ext4_fsblk_t err_blk = 0;
 	int ret;
 
 	ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, NULL, iloc,
@@ -4539,7 +4539,7 @@ static int __ext4_get_inode_loc_noinmem(struct inode *inode,
 
 int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
 {
-	ext4_fsblk_t err_blk;
+	ext4_fsblk_t err_blk = 0;
 	int ret;
 
 	ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, inode, iloc,