On 2023/9/11 10:51, Li Zetao wrote:
> There is a memory leak reported by kmemleak:
>
> unreferenced object 0xff11000105903b80 (size 64):
> comm "mount", pid 3382, jiffies 4295032021 (age 27.826s)
> hex dump (first 32 bytes):
> 04 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................
> ff ff ff ff 00 00 00 00 00 00 00 00 00 00 00 00 ................
> backtrace:
> [<ffffffffae86ac40>] __kmalloc_node+0x50/0x160
> [<ffffffffaf2486d8>] crypto_alloc_tfmmem.isra.0+0x38/0x110
> [<ffffffffaf2498e5>] crypto_create_tfm_node+0x85/0x2f0
> [<ffffffffaf24a92c>] crypto_alloc_tfm_node+0xfc/0x210
> [<ffffffffaedde777>] journal_init_common+0x727/0x1ad0
> [<ffffffffaede1715>] jbd2_journal_init_inode+0x2b5/0x500
> [<ffffffffaed786b5>] ext4_load_and_init_journal+0x255/0x2440
> [<ffffffffaed8b423>] ext4_fill_super+0x8823/0xa330
> ...
>
> The root cause was traced to an error handing path in journal_init_common()
> when malloc memory failed in register_shrinker(). The checksum driver is
> used to reference to checksum algorithm via cryptoapi and the user should
> release the memory when the driver is no longer needed or the journal
> initialization failed.
>
> Fix it by calling crypto_free_shash() on the "err_cleanup" error handing
> path in journal_init_common().
>
> Fixes: c30713084ba5 ("jbd2: move load_superblock() into journal_init_common()")
> Signed-off-by: Li Zetao <lizetao1@xxxxxxxxxx>
Thanks for the fix, it looks good to me.
Reviewed-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
> ---
> fs/jbd2/journal.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
> index 768fa05bcbed..30dec2bd2ecc 100644
> --- a/fs/jbd2/journal.c
> +++ b/fs/jbd2/journal.c
> @@ -1601,6 +1601,8 @@ static journal_t *journal_init_common(struct block_device *bdev,
>
> err_cleanup:
> percpu_counter_destroy(&journal->j_checkpoint_jh_count);
> + if (journal->j_chksum_driver)
> + crypto_free_shash(journal->j_chksum_driver);
> kfree(journal->j_wbuf);
> jbd2_journal_destroy_revoke(journal);
> journal_fail_superblock(journal);
>
