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  1. 15 Jul, 2022 2 commits
  3. 23 Jun, 2022 7 commits
  5. 17 Jun, 2022 26 commits
  7. 16 Jun, 2022 5 commits
    • Mikulas Patocka's avatar
      dm mirror log: round up region bitmap size to BITS_PER_LONG · 85e123c2
      Mikulas Patocka authored 
      The code in dm-log rounds up bitset_size to 32 bits. It then uses
find_next_zero_bit_le on the allocated region. find_next_zero_bit_le
accesses the bitmap using unsigned long pointers. So, on 64-bit
architectures, it may access 4 bytes beyond the allocated size.

Fix this bug by rounding up bitset_size to BITS_PER_LONG.

This bug was found by running the lvm2 testsuite with kasan.

Fixes: 29121bd0 ("[PATCH] dm mirror log: bitset_size fix")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
      85e123c2
    • Mikulas Patocka's avatar
      dm: fix narrow race for REQ_NOWAIT bios being issued despite no support · 1ee88de3
      Mikulas Patocka authored 
      Starting with the commit 63a225c9fd20, device mapper has an optimization
that it will take cheaper table lock (dm_get_live_table_fast instead of
dm_get_live_table) if the bio has REQ_NOWAIT. The bios with REQ_NOWAIT
must not block in the target request routine, if they did, we would be
blocking while holding rcu_read_lock, which is prohibited.

The targets that are suitable for REQ_NOWAIT optimization (and that don't
block in the map routine) have the flag DM_TARGET_NOWAIT set. Device
mapper will test if all the targets and all the devices in a table
support nowait (see the function dm_table_supports_nowait) and it will set
or clear the QUEUE_FLAG_NOWAIT flag on its request queue according to
this check.

There's a test in submit_bio_noacct: "if ((bio->bi_opf & REQ_NOWAIT) &&
!blk_queue_nowait(q)) goto not_supported" - this will make sure that
REQ_NOWAIT bios can't enter a request queue that doesn't support them.

This mechanism works to prevent REQ_NOWAIT bios from reaching dm targets
that don't support the REQ_NOWAIT flag (and that may block in the map
routine) - except that there is a small race condition:

submit_bio_noacct checks if the queue has the QUEUE_FLAG_NOWAIT without
holding any locks. Immediatelly after this check, the device mapper table
may be reloaded with a table that doesn't support REQ_NOWAIT (for example,
if we start moving the logical volume or if we activate a snapshot).
However the REQ_NOWAIT bio that already passed the check in
submit_bio_noacct would be sent to device mapper, where it could be
redirected to a dm target that doesn't support REQ_NOWAIT - the result is
sleeping while we hold rcu_read_lock.

In order to fix this race, we double-check if the target supports
REQ_NOWAIT while we hold the table lock (so that the table can't change
under us).

Fixes: 563a225c ("dm: introduce dm_{get,put}_live_table_bio called from dm_submit_bio")
Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
      1ee88de3
    • Mikulas Patocka's avatar
      dm: fix use-after-free in dm_put_live_table_bio · 5d7362d0
      Mikulas Patocka authored 
      dm_put_live_table_bio is called from the end of dm_submit_bio.
However, at this point, the bio may be already finished and the caller
may have freed the bio. Consequently, dm_put_live_table_bio accesses
the stale "bio" pointer.

Fix this bug by loading the bi_opf value and passing it to
dm_get_live_table_bio and dm_put_live_table_bio instead of the bio.

This bug was found by running the lvm2 testsuite with kasan.

Fixes: 563a225c ("dm: introduce dm_{get,put}_live_table_bio called from dm_submit_bio")
Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
      5d7362d0
    • Dave Airlie's avatar
      Merge tag 'drm-misc-fixes-2022-06-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes · 2f90ec12
      Dave Airlie authored 
      Two fixes for TTM, one for a NULL pointer dereference and one to make sure
the buffer is pinned prior to a bulk move, and a fix for a spurious
compiler warning.
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>

From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220616072519.qwrsefsemejefowu@houat
      2f90ec12
    • Bart Van Assche's avatar
      block/bfq: Enable I/O statistics · b96f3cab
      Bart Van Assche authored 
      BFQ uses io_start_time_ns. That member variable is only set if I/O
statistics are enabled. Hence this patch that enables I/O statistics
at the time BFQ is associated with a request queue.

Compile-tested only.
Reported-by: default avatarCixi Geng <cixi.geng1@unisoc.com>
Cc: Cixi Geng <cixi.geng1@unisoc.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Paolo Valente <paolo.valente@unimore.it>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarBart Van Assche <bvanassche@acm.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      b96f3cab
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