Hello,
syzbot found the following crash on:
HEAD commit: 8ada228a Add linux-next specific files for 20191011 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=14c30b1b600000 kernel config: https://syzkaller.appspot.com/x/.config?x=7cf4eed5fe42c31a dashboard link: https://syzkaller.appspot.com/bug?extid=e7ad70d406e74d8fc9d0 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1087d31b600000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15e27c53600000
The bug was bisected to:
commit 94e2ec3f7fef86506293a448273b2b4ee21e6195 Author: Oleg Vasilev omrigann@gmail.com Date: Mon Sep 30 15:59:24 2019 +0000
drm/vkms: prime import support
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=15ef2d57600000 final crash: https://syzkaller.appspot.com/x/report.txt?x=17ef2d57600000 console output: https://syzkaller.appspot.com/x/log.txt?x=13ef2d57600000
IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+e7ad70d406e74d8fc9d0@syzkaller.appspotmail.com Fixes: 94e2ec3f7fef ("drm/vkms: prime import support")
------------[ cut here ]------------ WARNING: CPU: 1 PID: 9040 at drivers/gpu/drm/vkms/vkms_gem.c:37 vkms_gem_free_object+0x92/0xb0 drivers/gpu/drm/vkms/vkms_gem.c:37 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 9040 Comm: syz-executor028 Not tainted 5.4.0-rc2-next-20191011 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x35 kernel/panic.c:582 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028 RIP: 0010:vkms_gem_free_object+0x92/0xb0 drivers/gpu/drm/vkms/vkms_gem.c:37 Code: 44 68 7f fd 49 8d bc 24 f8 01 00 00 e8 c7 8d 64 fd 4c 89 e7 e8 3f 39 ae ff 4c 89 e7 e8 f7 9a ba fd 41 5c 5d c3 e8 1e 68 7f fd <0f> 0b eb a2 e8 15 68 7f fd 0f 0b eb c8 e8 2c e7 ba fd eb b6 e8 25 RSP: 0018:ffff8880971df9e8 EFLAGS: 00010293 RAX: ffff8880989c2200 RBX: ffffffff894e5000 RCX: ffffffff83a1eda6 RDX: 0000000000000000 RSI: ffffffff83f3ab02 RDI: ffff8880a8c4fa78 RBP: ffff8880971df9f0 R08: ffff8880989c2200 R09: ffffed1012e3bf36 R10: ffffed1012e3bf35 R11: 0000000000000003 R12: ffff8880a8c4f800 R13: ffff8880a3ab8000 R14: ffffffff83f3aa70 R15: ffff8880a3ab8020 drm_gem_object_free+0x100/0x220 drivers/gpu/drm/drm_gem.c:983 kref_put include/linux/kref.h:65 [inline] drm_gem_object_put_unlocked drivers/gpu/drm/drm_gem.c:1017 [inline] drm_gem_object_put_unlocked+0x127/0x170 drivers/gpu/drm/drm_gem.c:1002 drm_gem_object_handle_put_unlocked+0x1ad/0x2d0 drivers/gpu/drm/drm_gem.c:239 drm_gem_object_release_handle+0x102/0x1c0 drivers/gpu/drm/drm_gem.c:261 idr_for_each+0x138/0x250 lib/idr.c:208 drm_gem_release+0x27/0x40 drivers/gpu/drm/drm_gem.c:939 drm_file_free.part.0+0x7f4/0xc00 drivers/gpu/drm/drm_file.c:244 drm_file_free drivers/gpu/drm/drm_file.c:213 [inline] drm_close_helper drivers/gpu/drm/drm_file.c:271 [inline] drm_release+0x286/0x3f0 drivers/gpu/drm/drm_file.c:443 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x904/0x2e60 kernel/exit.c:817 do_group_exit+0x135/0x360 kernel/exit.c:921 __do_sys_exit_group kernel/exit.c:932 [inline] __se_sys_exit_group kernel/exit.c:930 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:930 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x442bb8 Code: Bad RIP value. RSP: 002b:00007ffd8fdc0b98 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000442bb8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004c24c8 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 00000000004002e0 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d41a0 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds..
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