linux/block
Ken Xue 4fd41a8552 SCSI: Fix NULL pointer dereference in runtime PM
The routines in scsi_pm.c assume that if a runtime-PM callback is
invoked for a SCSI device, it can only mean that the device's driver
has asked the block layer to handle the runtime power management (by
calling blk_pm_runtime_init(), which among other things sets q->dev).

However, this assumption turns out to be wrong for things like the ses
driver.  Normally ses devices are not allowed to do runtime PM, but
userspace can override this setting.  If this happens, the kernel gets
a NULL pointer dereference when blk_post_runtime_resume() tries to use
the uninitialized q->dev pointer.

This patch fixes the problem by checking q->dev in block layer before
handle runtime PM. Since ses doesn't define any PM callbacks and call
blk_pm_runtime_init(), the crash won't occur.

This fixes Bugzilla #101371.
https://bugzilla.kernel.org/show_bug.cgi?id=101371

More discussion can be found from below link.
http://marc.info/?l=linux-scsi&m=144163730531875&w=2

Signed-off-by: Ken Xue <Ken.Xue@amd.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Xiangliang Yu <Xiangliang.Yu@amd.com>
Cc: James E.J. Bottomley <JBottomley@odin.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Michael Terry <Michael.terry@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-03 20:35:02 -07:00
..
partitions mac: validate mac_partition is within sector 2015-11-20 08:49:28 -07:00
bio-integrity.c block: blk_flush_integrity() for bio-based drivers 2015-10-21 14:43:44 -06:00
bio.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
blk-cgroup.c Merge branch 'for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2015-11-05 14:51:32 -08:00
blk-core.c SCSI: Fix NULL pointer dereference in runtime PM 2015-12-03 20:35:02 -07:00
blk-exec.c block: move PM request support to IDE 2015-05-05 13:40:42 -06:00
blk-flush.c Revert "blk-flush: Queue through IO scheduler when flush not required" 2015-11-25 10:12:54 -07:00
blk-integrity.c block, libnvdimm, nvme: provide a built-in blk_integrity nop profile 2015-10-21 14:43:45 -06:00
blk-ioc.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
blk-iopoll.c Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next 2014-06-03 12:57:53 -07:00
blk-lib.c block: re-add discard_granularity and alignment checks 2015-10-28 09:12:58 +09:00
blk-map.c block: Copy a user iovec if it includes gaps 2015-09-11 09:03:50 -06:00
blk-merge.c blk-merge: fix computing bio->bi_seg_front_size in case of single segment 2015-11-30 13:02:36 -07:00
blk-mq-cpu.c blk-mq: add file comments and update copyright notices 2014-05-28 10:15:41 -06:00
blk-mq-cpumap.c blk-mq: avoid inserting requests before establishing new mapping 2015-09-29 11:32:50 -06:00
blk-mq-sysfs.c block: add block polling support 2015-11-07 10:40:47 -07:00
blk-mq-tag.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
blk-mq-tag.h blk-mq: factor out a helper to iterate all tags for a request_queue 2015-10-01 10:10:57 +02:00
blk-mq.c blk-mq: fix calling unplug callbacks with preempt disabled 2015-11-20 20:29:45 -07:00
blk-mq.h blk-mq: mark __blk_mq_complete_request() static 2015-11-11 09:36:56 -07:00
blk-settings.c Merge branch 'for-4.3/core' of git://git.kernel.dk/linux-block 2015-09-02 13:10:25 -07:00
blk-softirq.c block: fix regression with block enabled tagging 2014-04-09 21:54:06 -06:00
blk-sysfs.c block: add block polling support 2015-11-07 10:40:47 -07:00
blk-tag.c block: support different tag allocation policy 2015-01-23 14:15:46 -07:00
blk-throttle.c cgroup: replace cgroup_on_dfl() tests in controllers with cgroup_subsys_on_dfl() 2015-09-18 11:56:28 -04:00
blk-timeout.c block: fix blk_abort_request for blk-mq drivers 2015-11-24 15:24:10 -07:00
blk.h block: protect rw_page against device teardown 2015-11-19 13:47:10 -08:00
bounce.c Merge branch 'for-linus' of git://git.kernel.dk/linux-block 2015-09-19 18:57:09 -07:00
bsg-lib.c
bsg.c block: Simplify bsg complete all 2015-02-04 09:57:52 -07:00
cfq-iosched.c cgroup: replace cgroup_on_dfl() tests in controllers with cgroup_subsys_on_dfl() 2015-09-18 11:56:28 -04:00
cmdline-parser.c
compat_ioctl.c block, bdi: an active gendisk always has a request_queue associated with it 2014-09-08 10:00:35 -06:00
deadline-iosched.c block: Stop abusing csd.list for fifo_time 2014-02-24 14:46:32 -08:00
elevator.c block: check bio_mergeable() early before merging 2015-10-21 15:00:54 -06:00
genhd.c block: Inline blk_integrity in struct gendisk 2015-10-21 14:42:42 -06:00
ioctl.c block: add an API for Persistent Reservations 2015-10-21 14:46:56 -06:00
ioprio.c pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode 2015-11-06 17:50:42 -08:00
Kconfig block: Add T10 Protection Information functions 2014-09-27 09:14:59 -06:00
Kconfig.iosched
Makefile block: Add T10 Protection Information functions 2014-09-27 09:14:59 -06:00
noop-iosched.c elevator: use list_{first,prev,next}_entry 2015-11-16 15:21:48 -07:00
partition-generic.c Return EBUSY from BLKRRPART for mounted whole-dev fs 2015-11-25 20:49:24 -07:00
scsi_ioctl.c mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM 2015-11-06 17:50:42 -08:00
t10-pi.c block: Consolidate static integrity profile properties 2015-10-21 14:42:38 -06:00