From: Qu Wenruo Date: Mon, 10 Oct 2022 10:36:07 +0000 (+0800) Subject: btrfs: raid56: avoid double freeing for rbio if full_stripe_write() failed X-Git-Tag: baikal/aarch64/sdk6.1~2730^2~6 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=65296633be02cfd903c0944e12ab7875fb9a887b;p=kernel.git btrfs: raid56: avoid double freeing for rbio if full_stripe_write() failed Currently if full_stripe_write() failed to allocate the pages for parity, it will call __free_raid_bio() first, then return -ENOMEM. But some caller of full_stripe_write() will also call __free_raid_bio() again, this would cause double freeing. And it's not a logically sound either, normally we should either free the memory at the same level where we allocated it, or let endio to handle everything. So this patch will solve the double freeing by make raid56_parity_write() to handle the error and free the rbio. Just like what we do in raid56_parity_recover(). Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 892005f756cfc..82c8e991300e3 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -1632,10 +1632,8 @@ static int full_stripe_write(struct btrfs_raid_bio *rbio) int ret; ret = alloc_rbio_parity_pages(rbio); - if (ret) { - __free_raid_bio(rbio); + if (ret) return ret; - } ret = lock_stripe_add(rbio); if (ret == 0) @@ -1823,8 +1821,10 @@ void raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc) */ if (rbio_is_full(rbio)) { ret = full_stripe_write(rbio); - if (ret) + if (ret) { + __free_raid_bio(rbio); goto fail; + } return; } @@ -1838,8 +1838,10 @@ void raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc) list_add_tail(&rbio->plug_list, &plug->rbio_list); } else { ret = __raid56_parity_write(rbio); - if (ret) + if (ret) { + __free_raid_bio(rbio); goto fail; + } } return;