bisecting fixing commit since a74d0e937a3acaea08ec0a7bfa047b8e0a6b6303 building syzkaller on 442206d76b974cca2d83ec763d4cf5ee829eb7d6 testing commit a74d0e937a3acaea08ec0a7bfa047b8e0a6b6303 with gcc (GCC) 8.1.0 kernel signature: da8d2fdc23fbe24b6b4e98931bbd757d697df590 all runs: crashed: general protection fault in __vb2_queue_free testing current HEAD 84f5ad468100f86d70096799e4ee716a17c2962f testing commit 84f5ad468100f86d70096799e4ee716a17c2962f with gcc (GCC) 8.1.0 kernel signature: 3d8b0703159eb6860aa7643ebc890cce90871522 all runs: crashed: general protection fault in __vb2_queue_free revisions tested: 2, total time: 23m45.651127339s (build: 16m8.280702892s, test: 6m46.220742263s) the crash still happens on HEAD commit msg: Linux 4.14.162 crash: general protection fault in __vb2_queue_free Out of memory: Kill process 6797 (syz-execprog) score 1 or sacrifice child Killed process 6811 (syz-executor.2) total-vm:37636kB, anon-rss:60kB, file-rss:0kB, shmem-rss:0kB oom_reaper: reaped process 6811 (syz-executor.2), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 6851 Comm: syz-executor.2 Not tainted 4.14.162-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888078a3e500 task.stack: ffff888090b90000 RIP: 0010:vb2_vmalloc_put_userptr+0x69/0x1e0 drivers/media/v4l2-core/videobuf2-vmalloc.c:136 RSP: 0018:ffff888090b979f0 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffc90005ebc000 RCX: ffffffff84238330 RDX: 0000000000000001 RSI: ffffed100f096cf2 RDI: 0000000000000009 RBP: ffff888090b97a18 R08: ffff88808b49de80 R09: 1ffffffff0de5654 R10: ffff888090b97aa8 R11: ffff888078a3e500 R12: ffff88808b49de80 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88808b49de88 FS: 00007f55b1c68700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200001c0 CR3: 000000008dfd3000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __vb2_buf_userptr_put drivers/media/v4l2-core/videobuf2-core.c:256 [inline] __vb2_free_mem drivers/media/v4l2-core/videobuf2-core.c:413 [inline] __vb2_queue_free+0x337/0x770 drivers/media/v4l2-core/videobuf2-core.c:454 vb2_core_queue_release+0x57/0x70 drivers/media/v4l2-core/videobuf2-core.c:2043 vb2_queue_release+0x9/0x10 drivers/media/v4l2-core/videobuf2-v4l2.c:669 v4l2_m2m_ctx_release+0x22/0x30 drivers/media/v4l2-core/v4l2-mem2mem.c:674 vim2m_release+0xcd/0x120 drivers/media/platform/vim2m.c:959 v4l2_release+0xeb/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:446 __fput+0x232/0x750 fs/file_table.c:210 ____fput+0x9/0x10 fs/file_table.c:244 task_work_run+0xe5/0x170 kernel/task_work.c:113 get_signal+0x148c/0x1b30 kernel/signal.c:2224 do_signal+0x7f/0x19a0 arch/x86/kernel/signal.c:814 exit_to_usermode_loop+0x114/0x1b0 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x416/0x5b0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4592c9 RSP: 002b:00007f55b1c67c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffff2 RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 00000000200001c0 RSI: 00000000c100565c RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f55b1c686d4 R13: 00000000004c4241 R14: 00000000004d7ee0 R15: 00000000ffffffff Code: 4c 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 76 01 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 6c 24 08 49 8d 7d 09 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 07 01 00 RIP: vb2_vmalloc_put_userptr+0x69/0x1e0 drivers/media/v4l2-core/videobuf2-vmalloc.c:136 RSP: ffff888090b979f0 ---[ end trace 179b755b7a67ff33 ]--- kobject: 'ip6gre0' (ffff88808e5673b0): kobject_cleanup, parent (null)