diff options
author | Dan Williams <dan.j.williams@intel.com> | 2021-06-08 01:52:43 +0200 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2021-06-09 17:09:22 +0200 |
commit | a624eb520390cecf644a8906c982fd53b2afcc49 (patch) | |
tree | 026d953a62a37486903e8a032a1a9a29dc7cbc5b | |
parent | rq-qos: fix missed wake-ups in rq_qos_throttle try two (diff) | |
download | linux-a624eb520390cecf644a8906c982fd53b2afcc49.tar.xz linux-a624eb520390cecf644a8906c982fd53b2afcc49.zip |
libnvdimm/pmem: Fix blk_cleanup_disk() usage
The queue_to_disk() helper can not be used after del_gendisk()
communicate @disk via the pgmap->owner.
Otherwise, queue_to_disk() returns NULL resulting in the splat below.
Kernel attempted to read user page (330) - exploit attempt? (uid: 0)
BUG: Kernel NULL pointer dereference on read at 0x00000330
Faulting instruction address: 0xc000000000906344
Oops: Kernel access of bad area, sig: 11 [#1]
[..]
NIP [c000000000906344] pmem_pagemap_cleanup+0x24/0x40
LR [c0000000004701d4] memunmap_pages+0x1b4/0x4b0
Call Trace:
[c000000022cbb9c0] [c0000000009063c8] pmem_pagemap_kill+0x28/0x40 (unreliable)
[c000000022cbb9e0] [c0000000004701d4] memunmap_pages+0x1b4/0x4b0
[c000000022cbba90] [c0000000008b28a0] devm_action_release+0x30/0x50
[c000000022cbbab0] [c0000000008b39c8] release_nodes+0x2f8/0x3e0
[c000000022cbbb60] [c0000000008ac440] device_release_driver_internal+0x190/0x2b0
[c000000022cbbba0] [c0000000008a8450] unbind_store+0x130/0x170
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Fixes: 87eb73b2ca7c ("nvdimm-pmem: convert to blk_alloc_disk/blk_cleanup_disk")
Link: http://lore.kernel.org/r/DFB75BA8-603F-4A35-880B-C5B23EF8FA7D@linux.vnet.ibm.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/162310994435.1571616.334551212901820961.stgit@dwillia2-desk3.amr.corp.intel.com
[axboe: fold in compile warning fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | drivers/nvdimm/pmem.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 31f3c4bd6f72..1e0615b8565e 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -335,10 +335,9 @@ static const struct attribute_group *pmem_attribute_groups[] = { static void pmem_pagemap_cleanup(struct dev_pagemap *pgmap) { - struct request_queue *q = - container_of(pgmap->ref, struct request_queue, q_usage_counter); + struct pmem_device *pmem = pgmap->owner; - blk_cleanup_disk(queue_to_disk(q)); + blk_cleanup_disk(pmem->disk); } static void pmem_release_queue(void *pgmap) @@ -427,6 +426,7 @@ static int pmem_attach_disk(struct device *dev, q = disk->queue; pmem->disk = disk; + pmem->pgmap.owner = pmem; pmem->pfn_flags = PFN_DEV; pmem->pgmap.ref = &q->q_usage_counter; if (is_nd_pfn(dev)) { |