Hello, syzbot found the following issue on: HEAD commit: 8515d05bf6bc Add linux-next specific files for 20220328 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1694e21b700000 kernel config: https://syzkaller.appspot.com/x/.config?x=530c68bef4e2b8a8 dashboard link: https://syzkaller.appspot.com/bug?extid=5c943fe38e86d615cac2 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1467313b700000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=121b7cb9700000 The issue was bisected to: commit 519f490db07e1a539490612f376487f61e48e39c Author: Christian König <christian.koenig@xxxxxxx> Date: Fri Mar 11 09:32:26 2022 +0000 dma-buf/sync-file: fix warning about fence containers bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1058277d700000 final oops: https://syzkaller.appspot.com/x/report.txt?x=1258277d700000 console output: https://syzkaller.appspot.com/x/log.txt?x=1458277d700000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5c943fe38e86d615cac2@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 519f490db07e ("dma-buf/sync-file: fix warning about fence containers") general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 1 PID: 3595 Comm: syz-executor814 Not tainted 5.17.0-next-20220328-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:dma_fence_array_first+0x78/0xb0 drivers/dma-buf/dma-fence-array.c:234 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 43 48 8b 9b 88 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 75 1b 4c 8b 23 e8 fa a9 e0 fc 4c 89 e0 5b 41 5c c3 45 RSP: 0018:ffffc90003a4fd48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff84980052 RDI: ffff888015c76388 RBP: ffff888015c76300 R08: 0000000000000000 R09: ffff888015c7633b R10: ffffffff8498f6ba R11: 0000000000000000 R12: ffff888015c76300 R13: ffff888015c76690 R14: 00000000c0383e04 R15: 0000000020001840 FS: 0000555556872300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001528 CR3: 000000001e82f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __dma_fence_unwrap_array include/linux/dma-fence-unwrap.h:42 [inline] dma_fence_unwrap_first include/linux/dma-fence-unwrap.h:57 [inline] sync_file_ioctl_fence_info drivers/dma-buf/sync_file.c:414 [inline] sync_file_ioctl+0x248/0x22c0 drivers/dma-buf/sync_file.c:477 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f6aae8951b9 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffedd290238 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6aae8951b9 RDX: 0000000020001840 RSI: 00000000c0383e04 RDI: 0000000000000007 RBP: 00007f6aae8591a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6aae859230 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:dma_fence_array_first+0x78/0xb0 drivers/dma-buf/dma-fence-array.c:234 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 43 48 8b 9b 88 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 75 1b 4c 8b 23 e8 fa a9 e0 fc 4c 89 e0 5b 41 5c c3 45 RSP: 0018:ffffc90003a4fd48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff84980052 RDI: ffff888015c76388 RBP: ffff888015c76300 R08: 0000000000000000 R09: ffff888015c7633b R10: ffffffff8498f6ba R11: 0000000000000000 R12: ffff888015c76300 R13: ffff888015c76690 R14: 00000000c0383e04 R15: 0000000020001840 FS: 0000555556872300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020001528 CR3: 000000001e82f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: df 48 89 fisttps -0x77(%rax) 3: fa cli 4: 48 c1 ea 03 shr $0x3,%rdx 8: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) c: 75 43 jne 0x51 e: 48 8b 9b 88 00 00 00 mov 0x88(%rbx),%rbx 15: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1c: fc ff df 1f: 48 89 da mov %rbx,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx * 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2a: 75 1b jne 0x47 2c: 4c 8b 23 mov (%rbx),%r12 2f: e8 fa a9 e0 fc callq 0xfce0aa2e 34: 4c 89 e0 mov %r12,%rax 37: 5b pop %rbx 38: 41 5c pop %r12 3a: c3 retq 3b: 45 rex.RB --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches