ext4: Fix memory leak fix when mounting an ext4 filesystem

The allocation of the ext4_group_info array was moved to a new
function ext4_mb_add_group_info() in commit 5f21b0e6 so that online
resize would use a common (and correct) codepath.  Unfortunately, the
call to the new ext4_mb_add_group_info() function was added without
removing the code which originally allocated the array.  This caused a
memory leak each time an ext4 filesystem was mounted.

The fix is simple; remove the code that did the original allocation,
since it is no longer needed.

Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index cd258463e2a9e017f949367b403d87332e5a3d24..cf9972090ad9ffa2a0cb8f35d4e41c5a5031f03a 100644 (file)
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2571,13 +2571,11 @@ static int ext4_mb_init_backend(struct super_block *sb)
 {
        ext4_group_t ngroups = ext4_get_groups_count(sb);
        ext4_group_t i;
-       int metalen;
        struct ext4_sb_info *sbi = EXT4_SB(sb);
        struct ext4_super_block *es = sbi->s_es;
        int num_meta_group_infos;
        int num_meta_group_infos_max;
        int array_size;
-       struct ext4_group_info **meta_group_info;
        struct ext4_group_desc *desc;
 
        /* This is the number of blocks used by GDT */
@@ -2622,22 +2620,6 @@ static int ext4_mb_init_backend(struct super_block *sb)
                goto err_freesgi;
        }
        EXT4_I(sbi->s_buddy_cache)->i_disksize = 0;
-
-       metalen = sizeof(*meta_group_info) << EXT4_DESC_PER_BLOCK_BITS(sb);
-       for (i = 0; i < num_meta_group_infos; i++) {
-               if ((i + 1) == num_meta_group_infos)
-                       metalen = sizeof(*meta_group_info) *
-                               (ngroups -
-                                       (i << EXT4_DESC_PER_BLOCK_BITS(sb)));
-               meta_group_info = kmalloc(metalen, GFP_KERNEL);
-               if (meta_group_info == NULL) {
-                       printk(KERN_ERR "EXT4-fs: can't allocate mem for a "
-                              "buddy group\n");
-                       goto err_freemeta;
-               }
-               sbi->s_group_info[i] = meta_group_info;
-       }
-
        for (i = 0; i < ngroups; i++) {
                desc = ext4_get_group_desc(sb, i, NULL);
                if (desc == NULL) {
@@ -2655,7 +2637,6 @@ err_freebuddy:
        while (i-- > 0)
                kfree(ext4_get_group_info(sb, i));
        i = num_meta_group_infos;
-err_freemeta:
        while (i-- > 0)
                kfree(sbi->s_group_info[i]);
        iput(sbi->s_buddy_cache);