Commit 024eab4d authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Theodore Ts'o
Browse files

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: default avatarCatalin Marinas <catalin.marinas@arm.com>
Tested-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent ab86e576

fs/ext4/mballoc.c

+0 −19
Original line number Diff line number Diff line
@@ -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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE