]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
btrfs: zoned: fix use-after-free due to race with dev replace
authorFilipe Manana <fdmanana@suse.com>
Wed, 8 May 2024 10:51:07 +0000 (11:51 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 21 Jun 2024 12:40:37 +0000 (14:40 +0200)
commita0cc006f4214b87e70983c692e05bb36c59b5752
treef03c68fc0d8accee1018e7651ccdd50d6d8307a4
parent3205e733b6dc24693452ecb46e2a2da02f6d3659
btrfs: zoned: fix use-after-free due to race with dev replace

commit 0090d6e1b210551e63cf43958dc7a1ec942cdde9 upstream.

While loading a zone's info during creation of a block group, we can race
with a device replace operation and then trigger a use-after-free on the
device that was just replaced (source device of the replace operation).

This happens because at btrfs_load_zone_info() we extract a device from
the chunk map into a local variable and then use the device while not
under the protection of the device replace rwsem. So if there's a device
replace operation happening when we extract the device and that device
is the source of the replace operation, we will trigger a use-after-free
if before we finish using the device the replace operation finishes and
frees the device.

Fix this by enlarging the critical section under the protection of the
device replace rwsem so that all uses of the device are done inside the
critical section.

CC: stable@vger.kernel.org # 6.1.x: 15c12fcc50a1: btrfs: zoned: introduce a zone_info struct in btrfs_load_block_group_zone_info
CC: stable@vger.kernel.org # 6.1.x: 09a46725cc84: btrfs: zoned: factor out per-zone logic from btrfs_load_block_group_zone_info
CC: stable@vger.kernel.org # 6.1.x: 9e0e3e74dc69: btrfs: zoned: factor out single bg handling from btrfs_load_block_group_zone_info
CC: stable@vger.kernel.org # 6.1.x: 87463f7e0250: btrfs: zoned: factor out DUP bg handling from btrfs_load_block_group_zone_info
CC: stable@vger.kernel.org # 6.1.x
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/btrfs/zoned.c