Hello, syzbot found the following issue on: HEAD commit: 642a16ca7994 Add linux-next specific files for 20240627 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=147914c6980000 kernel config: https://syzkaller.appspot.com/x/.config?x=ba15715f73169384 dashboard link: https://syzkaller.appspot.com/bug?extid=0b5c75599f1d872bea6f compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/72ed10c6e9be/disk-642a16ca.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f2ca81ede1c4/vmlinux-642a16ca.xz kernel image: https://storage.googleapis.com/syzbot-assets/af14c94fa854/bzImage-642a16ca.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0b5c75599f1d872bea6f@xxxxxxxxxxxxxxxxxxxxxxxxx Oops: general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] CPU: 0 UID: 60928 PID: 8680 Comm: syz.1.877 Not tainted 6.10.0-rc5-next-20240627-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:bpf_net_ctx_get_ri include/linux/filter.h:788 [inline] RIP: 0010:xdp_do_redirect+0x63/0xb40 net/core/filter.c:4423 Code: c3 08 18 00 00 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 ec 04 91 f8 4c 8b 23 4d 8d 74 24 38 4c 89 f3 48 c1 eb 03 <42> 0f b6 04 2b 84 c0 0f 85 fc 07 00 00 41 8b 2e 89 ee 83 e6 02 31 RSP: 0018:ffffc9001600f828 EFLAGS: 00010202 RAX: 1ffff110033f1301 RBX: 0000000000000007 RCX: 0000000000040000 RDX: ffffc9000ac74000 RSI: 0000000000000204 RDI: 0000000000000205 RBP: ffffc9001600f9b0 R08: 0000000000000005 R09: ffffffff866b25e9 R10: 0000000000000005 R11: ffff888019f88000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000038 R15: ffffc9001600faf0 FS: 00007fe5bc2366c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2411f23000 CR3: 000000005d692000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> tun_xdp_act+0xe9/0xb70 drivers/net/tun.c:1626 tun_build_skb drivers/net/tun.c:1716 [inline] tun_get_user+0x346d/0x4560 drivers/net/tun.c:1819 tun_chr_write_iter+0x113/0x1f0 drivers/net/tun.c:2048 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe5bb3746df Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 8b 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 8c 02 00 48 RSP: 002b:00007fe5bc236010 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe5bb503fa0 RCX: 00007fe5bb3746df RDX: 000000000000003e RSI: 0000000020000280 RDI: 00000000000000c8 RBP: 00007fe5bb3f6756 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000003e R11: 0000000000000293 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe5bb503fa0 R15: 00007ffe2c314948 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:bpf_net_ctx_get_ri include/linux/filter.h:788 [inline] RIP: 0010:xdp_do_redirect+0x63/0xb40 net/core/filter.c:4423 Code: c3 08 18 00 00 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 ec 04 91 f8 4c 8b 23 4d 8d 74 24 38 4c 89 f3 48 c1 eb 03 <42> 0f b6 04 2b 84 c0 0f 85 fc 07 00 00 41 8b 2e 89 ee 83 e6 02 31 RSP: 0018:ffffc9001600f828 EFLAGS: 00010202 RAX: 1ffff110033f1301 RBX: 0000000000000007 RCX: 0000000000040000 RDX: ffffc9000ac74000 RSI: 0000000000000204 RDI: 0000000000000205 RBP: ffffc9001600f9b0 R08: 0000000000000005 R09: ffffffff866b25e9 R10: 0000000000000005 R11: ffff888019f88000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000038 R15: ffffc9001600faf0 FS: 00007fe5bc2366c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2411f23000 CR3: 000000005d692000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: c3 ret 1: 08 18 or %bl,(%rax) 3: 00 00 add %al,(%rax) 5: 48 89 d8 mov %rbx,%rax 8: 48 c1 e8 03 shr $0x3,%rax c: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 11: 74 08 je 0x1b 13: 48 89 df mov %rbx,%rdi 16: e8 ec 04 91 f8 call 0xf8910507 1b: 4c 8b 23 mov (%rbx),%r12 1e: 4d 8d 74 24 38 lea 0x38(%r12),%r14 23: 4c 89 f3 mov %r14,%rbx 26: 48 c1 eb 03 shr $0x3,%rbx * 2a: 42 0f b6 04 2b movzbl (%rbx,%r13,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 fc 07 00 00 jne 0x833 37: 41 8b 2e mov (%r14),%ebp 3a: 89 ee mov %ebp,%esi 3c: 83 e6 02 and $0x2,%esi 3f: 31 .byte 0x31 --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
