Hello,
Le 20/09/2022 à 03:07, yebin a écrit :
On 2022/9/20 2:40, Damien Guibouret wrote:
Hello,
Le 19/09/2022 à 16:40, Ye Bin a écrit :
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.
Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx>
---
fs/ext4/fast_commit.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 9217a588afd1..cc8c8db075ba 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -1677,15 +1677,17 @@ int ext4_fc_record_regions(struct super_block
*sb, int ino,
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)
Would it not be safer to restore state->fc_regions_size to its
previous value in that case to keep consistency between size value and
allocated size (or to update state->fc_regions_size only after
allocation as it is done in second part of this patch) ?
Actually, If 'ext4_fc_record_regions()' return -ENOMEM, then will stop
replay journal.
'state->fc_regions_size' will not be used any more, so it's safe.
There are at least two calls in ext4_ext_clear_bb (ext4/extents.c) that
do not check for return code of ext4_fc_record_regions. But perhaps
these are these calls that should be fixed.
return -ENOMEM;
+ state->fc_regions = fc_regions;
}
region = &state->fc_regions[state->fc_regions_used++];
region->ino = ino;
Regards,
Damien