In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
drm\/imagination: Fix double call to drm_sched_entity_fini()<\/p>\n
Call sequence of double call:
\npvr_context_destroy
\n\u2003\u2003pvr_context_kill_queues
\n\u2003\u2003\u2003\u2003pvr_queue_kill
\n\u2003\u2003\u2003\u2003\u2003\u2003drm_sched_entity_destroy
\n\u2003\u2003\u2003\u2003\u2003\u2003\u2003\u2003drm_sched_entity_fini \/\/ here
\n\u2003\u2003pvr_context_put
\n\u2003\u2003\u2003\u2003kref_put(…, pvr_context_release)
\n\u2003\u2003\u2003\u2003\u2003\u2003pvr_context_destroy_queues
\n\u2003\u2003\u2003\u2003\u2003\u2003\u2003\u2003pvr_queue_destroy
\n\u2003\u2003\u2003\u2003\u2003\u2003\u2003\u2003\u2003\u2003drm_sched_entity_fini \/\/ here<\/p>\n
Call to drm_sched_entity_destroy() from pvr_context_kill_queues() calls
\ndrm_sched_entity_flush() + drm_sched_entity_fini().
\ndrm_sched_entity_flush() ensures all pending jobs are completed and
\ndrm_sched_entity_fini() ensures no further submission is allowed as
\nper expectation from pvr_context_kill_queues(). Double call to
\ndrm_sched_entity_fini() is misuse of the API so keep call only in
\npvr_context_create() failure path.<\/p>\n
Stack trace for issue with addition of refcounting for DRM entity
\nstats in commit fd177135f0e6 (“drm\/sched: Account entity GPU time”):<\/p>\n
[ 789.490527] ————[ cut here ]————
\n[ 789.490559] refcount_t: underflow; use-after-free.
\n[ 789.490657] WARNING: lib\/refcount.c:28 at refcount_warn_saturate+0xf4\/0x144, CPU#0: kworker\/u16:1\/440
\n[ 789.490695] Modules linked in: powervr drm_gpuvm drm_exec gpu_sched drm_shmem_helper xhci_plat_hcd xhci_hcd dwc3 usbcore usb_common snd_soc_simple_card snd_soc_simple_card_utils sa2ul sha512 sha256 dwc3_am62 sha1 authenc rti_wdt libsha512 at24 sch_fq_codel fuse dm_mod ipv6
\n[ 789.490798] CPU: 0 UID: 0 PID: 440 Comm: kworker\/u16:1 Not tainted 7.0.0-rc7-02049-g5e2c0700091b #22 PREEMPT
\n[ 789.490809] Hardware name: Texas Instruments AM625 SK (DT)
\n[ 789.490815] Workqueue: powervr-sched pvr_queue_fence_release_work [powervr]
\n[ 789.490868] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=–)
\n[ 789.490876] pc : refcount_warn_saturate+0xf4\/0x144
\n[ 789.490884] lr : refcount_warn_saturate+0xf4\/0x144
\n[ 789.490892] sp : ffff8000822cbcc0
\n[ 789.490895] x29: ffff8000822cbcc0 x28: 0000000000000000 x27: 0000000000000000
\n[ 789.490909] x26: 0000000000000000 x25: ffff800081b1e338 x24: ffff000004541405
\n[ 789.490922] x23: ffff000004bea950 x22: ffff00000042e400 x21: ffff000007123e30
\n[ 789.490935] x20: ffff000007123000 x19: ffff000007a80d50 x18: fffffffffffe7768
\n[ 789.490948] x17: 74736574202c6e6f x16: 697461746e656d65 x15: ffff800081b269f0
\n[ 789.490962] x14: 0000000000000030 x13: ffff800081b26a70 x12: 0000000000000211
\n[ 789.490975] x11: 00000000000000c0 x10: 0000000000000b50 x9 : ffff8000822cbb30
\n[ 789.490988] x8 : ffff0000014e7bb0 x7 : ffff00007725e780 x6 : 0000000372a05f49
\n[ 789.491001] x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000010
\n[ 789.491013] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000014e7000
\n[ 789.491027] Call trace:
\n[ 789.491032] refcount_warn_saturate+0xf4\/0x144 (P)
\n[ 789.491043] drm_sched_entity_fini+0x164\/0x18c [gpu_sched]
\n[ 789.491081] pvr_queue_destroy+0x64\/0x134 [powervr]
\n[ 789.491110] pvr_context_destroy_queues+0x34\/0x64 [powervr]
\n[ 789.491138] pvr_context_release+0x70\/0xac [powervr]
\n[ 789.491166] pvr_context_put.part.0+0x5c\/0x7c [powervr]
\n[ 789.491193] pvr_context_put+0x14\/0x24 [powervr]
\n[ 789.491221] pvr_queue_fence_release_work+0x20\/0x38 [powervr]
\n[ 789.491249] process_one_work+0x160\/0x4c4
\n[ 789.491264] worker_thread+0x188\/0x310
\n[ 789.491276] kthread+0x130\/0x13c
\n[ 789.491287] ret_from_fork+0x10\/0x20
\n[ 789.491300] —[ end trace 0000000000000000 ]—<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
drm\/imagination: Fix double call to drm_sched_entity_fini()<\/p>\n
Call sequence of double call:
\npvr_context_destroy
\n\u2003\u2003pvr_context_kill_q<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-5402","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/5402","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5402"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5402"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5402"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}