bisecting cause commit starting from 3f667b5d4053ad54aee13dab5c94f04ff75ddfdf building syzkaller on 44068e196185e2f5a7c94629b6245cdde008b140 testing commit 3f667b5d4053ad54aee13dab5c94f04ff75ddfdf compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 7602b70fbb89813a228ca0cd81c4ac0495ec6965b0162072797bd961447e4cb2 run #0: OK run #1: OK run #2: OK run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #10: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #11: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #12: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #13: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #14: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #15: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #16: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #17: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #18: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #19: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle testing release v5.15 testing commit 8bb7eca972ad531c9b149c0a51ab43a417385813 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 71323c101898a9d6190815ff9f0f1d0fc16010a2b4108dab910da9879ec0438d all runs: OK # git bisect start 3f667b5d4053ad54aee13dab5c94f04ff75ddfdf 8bb7eca972ad531c9b149c0a51ab43a417385813 Bisecting: 7456 revisions left to test after this (roughly 13 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [43e1b12927276cde8052122a24ff796649f09d60] Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost testing commit 43e1b12927276cde8052122a24ff796649f09d60 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 785815b5e49062bdd4dfbd45e2ff9b51cb2ced0839d251b61500c50ceefe9473 run #0: OK run #1: OK run #2: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 43e1b12927276cde8052122a24ff796649f09d60 Bisecting: 2910 revisions left to test after this (roughly 12 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [fc02cb2b37fe2cbf1d3334b9f0f0eab9431766c4] Merge tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next testing commit fc02cb2b37fe2cbf1d3334b9f0f0eab9431766c4 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 01b7cdf53ecdccaf832bca09f6796b0c07689e823a30c9c6f3834d2c5f22dacb all runs: OK # git bisect good fc02cb2b37fe2cbf1d3334b9f0f0eab9431766c4 Bisecting: 1628 revisions left to test after this (roughly 11 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [d9bd054177fbd2c4762546aec40fc3071bfe4cc0] Merge tag 'amd-drm-next-5.16-2021-10-29' of https://gitlab.freedesktop.org/agd5f/linux into drm-next testing commit d9bd054177fbd2c4762546aec40fc3071bfe4cc0 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 6f3216903d1fc38254cc6d158ee92eee0672ed461d57e745f4dad9fdfc62b2e7 run #0: OK run #1: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #2: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad d9bd054177fbd2c4762546aec40fc3071bfe4cc0 Bisecting: 695 revisions left to test after this (roughly 9 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [797d72ce8e0f8fa8a808cb189b5411046432cfd3] Merge tag 'drm-misc-next-2021-10-06' of git://anongit.freedesktop.org/drm/drm-misc into drm-next testing commit 797d72ce8e0f8fa8a808cb189b5411046432cfd3 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 69e54a1a78545152617daa56f187305906c6da7f0db5fa09c85b77ff7e083ffa all runs: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 797d72ce8e0f8fa8a808cb189b5411046432cfd3 Bisecting: 291 revisions left to test after this (roughly 8 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [1e3944578b749449bd7fa6bf0bae4c3d3f5f1733] Merge tag 'amd-drm-next-5.16-2021-09-27' of https://gitlab.freedesktop.org/agd5f/linux into drm-next testing commit 1e3944578b749449bd7fa6bf0bae4c3d3f5f1733 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: a59fd0b3455e11c4c1d0b570bcda4c71da67c98638fcd854cea232b2f8bdad89 run #0: OK run #1: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #2: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 1e3944578b749449bd7fa6bf0bae4c3d3f5f1733 Bisecting: 146 revisions left to test after this (roughly 7 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [22f4f4faf337d5fb2d2750aff13215726814273e] drm/amdkfd: fix svm_migrate_fini warning testing commit 22f4f4faf337d5fb2d2750aff13215726814273e compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 00925375448245f329a35e95fe13d590f3b95ce8ea3dcea2a625cdfe2249195f all runs: OK # git bisect good 22f4f4faf337d5fb2d2750aff13215726814273e Bisecting: 73 revisions left to test after this (roughly 6 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [98cca519df6da699240403721f5d251ecf702b3b] drm/ttm: cleanup ttm_resource_compat testing commit 98cca519df6da699240403721f5d251ecf702b3b compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 5edfa76af63146229dfd8b0b396c8da64302a3549175405833e5bca18c76b8f2 all runs: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 98cca519df6da699240403721f5d251ecf702b3b Bisecting: 36 revisions left to test after this (roughly 5 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [5e12f7ea4aa04d1ffbb08c899845efd74c173aaa] drm: v3d: correct reference to config ARCH_BRCMSTB testing commit 5e12f7ea4aa04d1ffbb08c899845efd74c173aaa compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 5e13c29aa04383a8e2dc2bfbd26867bb108bb01a4886ce4d96518db6f0d9236a run #0: OK run #1: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #2: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 5e12f7ea4aa04d1ffbb08c899845efd74c173aaa Bisecting: 17 revisions left to test after this (roughly 4 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [7f16d0f3b8e2d13f940e944cd17044ca8eeb8b32] drm/bridge: anx7625: Propagate errors from sp_tx_rst_aux() testing commit 7f16d0f3b8e2d13f940e944cd17044ca8eeb8b32 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 5160948310399c3ccde109c48bdf0692e7c537ca0734de339c5a94f62c99bbf9 run #0: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #1: OK run #2: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 7f16d0f3b8e2d13f940e944cd17044ca8eeb8b32 Bisecting: 8 revisions left to test after this (roughly 3 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [c1d3cfbc41a15d3eadde760c00fe6ce58a1d4e29] drm/tegra: Use fourcc_mod_is_vendor() helper testing commit c1d3cfbc41a15d3eadde760c00fe6ce58a1d4e29 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 67a62855e9ba67d48f70a6a230c23b1a6ecd2cf7f959f36fd68a7f57e4d1e548 all runs: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad c1d3cfbc41a15d3eadde760c00fe6ce58a1d4e29 Bisecting: 4 revisions left to test after this (roughly 2 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [8b4e02c70fca482c5b947d8ba92b45093b4390e7] drm/panel: Add DT bindings for Samsung S6D27A1 display panel testing commit 8b4e02c70fca482c5b947d8ba92b45093b4390e7 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: e68dc1f5da78d4683a4c9df97bda8881586d73174a1f4d64279e66e34a38a059 run #0: OK run #1: OK run #2: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 8b4e02c70fca482c5b947d8ba92b45093b4390e7 Bisecting: 1 revision left to test after this (roughly 1 step) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [804b6e5ee613b019b942ba6be52cccecd9d33655] drm/shmem-helpers: Allocate wc pages on x86 testing commit 804b6e5ee613b019b942ba6be52cccecd9d33655 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 33470fba136e375b491744e1dfdb478ac4bce98ba93b6d8935d49c64df644fe6 all runs: OK # git bisect good 804b6e5ee613b019b942ba6be52cccecd9d33655 Bisecting: 0 revisions left to test after this (roughly 0 steps) warning: unable to access '/syzkaller/.config/git/ignore': Permission denied warning: unable to access '/syzkaller/.config/git/attributes': Permission denied [45d9c8dde4cd8589f9180309ec60f0da2ce486e4] drm/vgem: use shmem helpers testing commit 45d9c8dde4cd8589f9180309ec60f0da2ce486e4 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: e68dc1f5da78d4683a4c9df97bda8881586d73174a1f4d64279e66e34a38a059 run #0: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #1: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #2: OK run #3: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #4: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #5: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #6: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #7: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #8: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle run #9: crashed: KASAN: use-after-free Read in drm_gem_object_release_handle # git bisect bad 45d9c8dde4cd8589f9180309ec60f0da2ce486e4 warning: unable to access '/syzkaller/.config/git/attributes': Permission denied 45d9c8dde4cd8589f9180309ec60f0da2ce486e4 is the first bad commit commit 45d9c8dde4cd8589f9180309ec60f0da2ce486e4 Author: Daniel Vetter Date: Thu Aug 12 15:14:12 2021 +0200 drm/vgem: use shmem helpers Aside from deleting lots of code the real motivation here is to switch the mmap over to VM_PFNMAP, to be more consistent with what real gpu drivers do. They're all VM_PFNMAP, which means get_user_pages doesn't work, and even if you try and there's a struct page behind that, touching it and mucking around with its refcount can upset drivers real bad. v2: Review from Thomas: - sort #include - drop more dead code that I didn't spot somehow v3: select DRM_GEM_SHMEM_HELPER to make it build (intel-gfx-ci) v4: I got tricked by 0cf2ef46c6c0 ("drm/shmem-helper: Use cached mappings by default"), and we need WC in vgem because vgem doesn't have explicit begin/end cpu access ioctls. Also add a comment why exactly vgem has to use wc. v5: Don't set obj->base.funcs, it will default to drm_gem_shmem_funcs (Thomas) v6: vgem also needs an MMU for remapping v7: I absolutely butchered the rebases over the vgem mmap change and revert and broke the patch. Actually go back to v6 from before the vgem mmap changes. Cc: Thomas Zimmermann Acked-by: Thomas Zimmermann Cc: John Stultz Cc: Sumit Semwal Cc: "Christian König" Signed-off-by: Daniel Vetter Cc: Melissa Wen Cc: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20210812131412.2487363-4-daniel.vetter@ffwll.ch drivers/gpu/drm/Kconfig | 5 +- drivers/gpu/drm/vgem/vgem_drv.c | 342 ++-------------------------------------- 2 files changed, 16 insertions(+), 331 deletions(-) culprit signature: e68dc1f5da78d4683a4c9df97bda8881586d73174a1f4d64279e66e34a38a059 parent signature: 33470fba136e375b491744e1dfdb478ac4bce98ba93b6d8935d49c64df644fe6 revisions tested: 15, total time: 3h12m14.481865286s (build: 2h26m48.78948983s, test: 43m47.006347772s) first bad commit: 45d9c8dde4cd8589f9180309ec60f0da2ce486e4 drm/vgem: use shmem helpers recipients (to): ["daniel.vetter@ffwll.ch" "daniel.vetter@intel.com" "tzimmermann@suse.de"] recipients (cc): [] crash: KASAN: use-after-free Read in drm_gem_object_release_handle RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffc000 RBP: 00007ffdf4ae0920 R08: 0000000000000003 R09: 0000000100000000 R10: 0000000000000012 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ================================================================== BUG: KASAN: use-after-free in drm_gem_object_release_handle+0xd1/0xf0 drivers/gpu/drm/drm_gem.c:252 Read of size 8 at addr ffff88801d68fa28 by task syz-executor655/5870 CPU: 0 PID: 5870 Comm: syz-executor655 Not tainted 5.14.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x57/0x7d lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 drm_gem_object_release_handle+0xd1/0xf0 drivers/gpu/drm/drm_gem.c:252 idr_for_each+0xf5/0x1d0 lib/idr.c:208 drm_gem_release+0x17/0x20 drivers/gpu/drm/drm_gem.c:930 drm_file_free.part.0+0x7a1/0xb60 drivers/gpu/drm/drm_file.c:281 drm_release+0x1bb/0x4b0 drivers/gpu/drm/drm_file.c:495 __fput+0x209/0x870 fs/file_table.c:280 task_work_run+0xc0/0x160 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0x9fe/0x24e0 kernel/exit.c:825 do_group_exit+0xe7/0x290 kernel/exit.c:922 __do_sys_exit_group kernel/exit.c:933 [inline] __se_sys_exit_group kernel/exit.c:931 [inline] __x64_sys_exit_group+0x35/0x40 kernel/exit.c:931 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f5cbd9759e9 Code: Unable to access opcode bytes at RIP 0x7f5cbd9759bf. RSP: 002b:00007ffdf4ae08f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f5cbd9e93f0 RCX: 00007f5cbd9759e9 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000100000000 R10: 0000000000000012 R11: 0000000000000246 R12: 00007f5cbd9e93f0 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 Allocated by task 5870: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] vgem_gem_create_object+0x35/0x90 drivers/gpu/drm/vgem/vgem_drv.c:98 __drm_gem_shmem_create+0x72/0x3e0 drivers/gpu/drm/drm_gem_shmem_helper.c:52 drm_gem_shmem_create drivers/gpu/drm/drm_gem_shmem_helper.c:114 [inline] drm_gem_shmem_create_with_handle+0x19/0x90 drivers/gpu/drm/drm_gem_shmem_helper.c:420 drm_gem_shmem_dumb_create+0x131/0x270 drivers/gpu/drm/drm_gem_shmem_helper.c:536 drm_ioctl_kernel+0x1c9/0x260 drivers/gpu/drm/drm_ioctl.c:795 drm_ioctl+0x444/0x8f0 drivers/gpu/drm/drm_ioctl.c:898 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x11f/0x190 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 5870: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kfree+0xeb/0x650 mm/slub.c:4262 kref_put include/linux/kref.h:65 [inline] __drm_gem_object_put include/drm/drm_gem.h:371 [inline] drm_gem_object_put include/drm/drm_gem.h:384 [inline] drm_gem_mmap+0x3be/0x4e0 drivers/gpu/drm/drm_gem.c:1132 call_mmap include/linux/fs.h:2119 [inline] mmap_region+0xa3c/0x14e0 mm/mmap.c:1808 do_mmap+0x5d3/0xfc0 mm/mmap.c:1584 vm_mmap_pgoff+0x163/0x210 mm/util.c:519 ksys_mmap_pgoff+0x3be/0x5f0 mm/mmap.c:1635 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88801d68f800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 552 bytes inside of 1024-byte region [ffff88801d68f800, ffff88801d68fc00) The buggy address belongs to the page: page:ffffea000075a200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d688 head:ffffea000075a200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff88800fc41dc0 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, ts 5555902984, free_ts 0 prep_new_page mm/page_alloc.c:2436 [inline] get_page_from_freelist+0xa6f/0x2f50 mm/page_alloc.c:4169 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5391 alloc_page_interleave+0xf/0x1c0 mm/mempolicy.c:2119 alloc_slab_page mm/slub.c:1688 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1828 new_slab mm/slub.c:1891 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2800 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] __kmalloc_node_track_caller+0x2e3/0x360 mm/slub.c:4648 alloc_dr drivers/gpu/drm/drm_managed.c:95 [inline] drmm_kmalloc+0x7e/0x1f0 drivers/gpu/drm/drm_managed.c:192 drmm_kzalloc include/drm/drm_managed.h:61 [inline] __drmm_universal_plane_alloc+0x141/0x260 drivers/gpu/drm/drm_plane.c:430 vkms_plane_init+0x64/0xc0 drivers/gpu/drm/vkms/vkms_plane.c:189 vkms_output_init+0x27/0x440 drivers/gpu/drm/vkms/vkms_output.c:46 vkms_modeset_init drivers/gpu/drm/vkms/vkms_drv.c:158 [inline] vkms_create drivers/gpu/drm/vkms/vkms_drv.c:200 [inline] vkms_init+0x4bb/0x54c drivers/gpu/drm/vkms/vkms_drv.c:233 do_one_initcall+0xbe/0x440 init/main.c:1282 do_initcall_level init/main.c:1355 [inline] do_initcalls init/main.c:1371 [inline] do_basic_setup init/main.c:1391 [inline] kernel_init_freeable+0x5b2/0x60c init/main.c:1593 kernel_init+0x14/0x120 init/main.c:1485 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 page_owner free stack trace missing Memory state around the buggy address: ffff88801d68f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801d68f980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801d68fa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801d68fa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801d68fb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================