This is a note to let you know that I've just added the patch titled drm/hisilicon: Fix use-after-free to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-hisilicon-fix-use-after-free.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2c59dff4b4b02f28bfd9a7474fb3ddce49da4ffd Author: Tian Tao <tiantao6@xxxxxxxxxxxxx> Date: Mon Dec 14 18:32:53 2020 +0800 drm/hisilicon: Fix use-after-free [ Upstream commit c855af2f9c5c60760fd1bed7889a81bc37d2591d ] Fix the problem of dev being released twice. ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 75 PID: 15700 at lib/refcount.c:28 refcount_warn_saturate+0xd4/0x150 CPU: 75 PID: 15700 Comm: rmmod Tainted: G E 5.10.0-rc3+ #3 Hardware name: Huawei TaiShan 200 (Model 2280)/BC82AMDDA, BIOS 0.88 07/24/2019 pstate: 40400009 (nZcv daif +PAN -UAO -TCO BTYPE=--) pc : refcount_warn_saturate+0xd4/0x150 lr : refcount_warn_saturate+0xd4/0x150 sp : ffff2028150cbc00 x29: ffff2028150cbc00 x28: ffff2028150121c0 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000003 x23: 0000000000000000 x22: ffff2028150cbc90 x21: ffff2020038a30a8 x20: ffff2028150cbc90 x19: ffff0020cd938020 x18: 0000000000000010 x17: 0000000000000000 x16: 0000000000000000 x15: ffffffffffffffff x14: ffff2028950cb88f x13: ffff2028150cb89d x12: 0000000000000000 x11: 0000000005f5e0ff x10: ffff2028150cb800 x9 : 00000000ffffffd0 x8 : 75203b776f6c6672 x7 : ffff800011a6f7c8 x6 : 0000000000000001 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : ffff202ffe2f9dc0 x1 : ffffa02fecf40000 x0 : 0000000000000026 Call trace: refcount_warn_saturate+0xd4/0x150 devm_drm_dev_init_release+0x50/0x70 devm_action_release+0x20/0x30 release_nodes+0x13c/0x218 devres_release_all+0x80/0x170 device_release_driver_internal+0x128/0x1f0 driver_detach+0x6c/0xe0 bus_remove_driver+0x74/0x100 driver_unregister+0x34/0x60 pci_unregister_driver+0x24/0xd8 hibmc_pci_driver_exit+0x14/0xe858 [hibmc_drm] __arm64_sys_delete_module+0x1fc/0x2d0 el0_svc_common.constprop.3+0xa8/0x188 do_el0_svc+0x80/0xa0 el0_sync_handler+0x8c/0xb0 el0_sync+0x15c/0x180 CPU: 75 PID: 15700 Comm: rmmod Tainted: G E 5.10.0-rc3+ #3 Hardware name: Huawei TaiShan 200 (Model 2280)/BC82AMDDA, BIOS 0.88 07/24/2019 Call trace: dump_backtrace+0x0/0x208 show_stack+0x2c/0x40 dump_stack+0xd8/0x10c __warn+0xac/0x128 report_bug+0xcc/0x180 bug_handler+0x24/0x78 call_break_hook+0x80/0xa0 brk_handler+0x28/0x68 do_debug_exception+0x9c/0x148 el1_sync_handler+0x7c/0x128 el1_sync+0x80/0x100 refcount_warn_saturate+0xd4/0x150 devm_drm_dev_init_release+0x50/0x70 devm_action_release+0x20/0x30 release_nodes+0x13c/0x218 devres_release_all+0x80/0x170 device_release_driver_internal+0x128/0x1f0 driver_detach+0x6c/0xe0 bus_remove_driver+0x74/0x100 driver_unregister+0x34/0x60 pci_unregister_driver+0x24/0xd8 hibmc_pci_driver_exit+0x14/0xe858 [hibmc_drm] __arm64_sys_delete_module+0x1fc/0x2d0 el0_svc_common.constprop.3+0xa8/0x188 do_el0_svc+0x80/0xa0 el0_sync_handler+0x8c/0xb0 el0_sync+0x15c/0x180 ---[ end trace 00718630d6e5ff18 ]--- Signed-off-by: Tian Tao <tiantao6@xxxxxxxxxxxxx> Acked-by: Thomas Zimmermann <tzimmermann@xxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/1607941973-32287-1-git-send-email-tiantao6@xxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c index c103005b0a33..a34ef5ec7d42 100644 --- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c @@ -376,7 +376,6 @@ static void hibmc_pci_remove(struct pci_dev *pdev) drm_dev_unregister(dev); hibmc_unload(dev); - drm_dev_put(dev); } static struct pci_device_id hibmc_pci_table[] = {