[PATCH 5.19 135/717] ext4: fix potential memory leak in ext4_fc_record_regions()

Greg Kroah-Hartman
2022-10-22T08:02:36Z

From: Ye Bin <yebin10@huawei.com>

commit 7069d105c1f15c442b68af43f7fde784f3126739 upstream.

As krealloc may return NULL, in this case 'state->fc_regions' may not be
freed by krealloc, but 'state->fc_regions' already set NULL. Then will
lead to 'state->fc_regions' memory leak.

Cc: stable@kernel.org
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220921064040.3693255-3-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ext4/fast_commit.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -1687,15 +1687,17 @@ int ext4_fc_record_regions(struct super_
if (replay && state->fc_regions_used != state->fc_regions_valid)
state->fc_regions_used = state->fc_regions_valid;
if (state->fc_regions_used == state->fc_regions_size) {
+ struct ext4_fc_alloc_region *fc_regions;
+
state->fc_regions_size +=
EXT4_FC_REPLAY_REALLOC_INCREMENT;
- state->fc_regions = krealloc(
- state->fc_regions,
- state->fc_regions_size *
- sizeof(struct ext4_fc_alloc_region),
- GFP_KERNEL);
- if (!state->fc_regions)
+ fc_regions = krealloc(state->fc_regions,
+ state->fc_regions_size *
+ sizeof(struct ext4_fc_alloc_region),
+ GFP_KERNEL);
+ if (!fc_regions)
return -ENOMEM;
+ state->fc_regions = fc_regions;
}
region = &state->fc_regions[state->fc_regions_used++];
region->ino = ino;