syzbot has found a reproducer for the following issue on: HEAD commit: 0b58e108042b Add linux-next specific files for 20240703 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=11ee3e81980000 kernel config: https://syzkaller.appspot.com/x/.config?x=ed034204f2e40e53 dashboard link: https://syzkaller.appspot.com/bug?extid=5ae46b237278e2369cac compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15a6e781980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=165e6db9980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1d079762feae/disk-0b58e108.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e53996c8d8c2/vmlinux-0b58e108.xz kernel image: https://storage.googleapis.com/syzbot-assets/a0bf21cdd844/bzImage-0b58e108.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5ae46b237278e2369cac@xxxxxxxxxxxxxxxxxxxxxxxxx Oops: stack segment: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 5100 Comm: syz-executor326 Not tainted 6.10.0-rc6-next-20240703-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:____bpf_xdp_redirect net/core/filter.c:4561 [inline] RIP: 0010:bpf_xdp_redirect+0x59/0x1a0 net/core/filter.c:4559 Code: 81 c3 00 18 00 00 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 b5 18 90 f8 48 8b 1b 4c 8d 63 38 4c 89 e5 48 c1 ed 03 <42> 0f b6 44 2d 00 84 c0 0f 85 d0 00 00 00 45 8b 34 24 44 89 f6 83 RSP: 0018:ffffc900033bf6f8 EFLAGS: 00010202 RAX: 1ffff11004549e40 RBX: 0000000000000000 RCX: ffff888022a4da00 RDX: 0000000000000000 RSI: 0000000002000000 RDI: ffffc900033bf900 RBP: 0000000000000007 R08: ffffffff895fff80 R09: 1ffff110172a8938 R10: dffffc0000000000 R11: ffffed10172a8939 R12: 0000000000000038 R13: dffffc0000000000 R14: 1ffff92000677f21 R15: 0000000002000000 FS: 000055557e4d4380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000f000 CR3: 000000007abc8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> bpf_prog_56e821181540367a+0x1d/0x1f __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run_xdp include/net/xdp.h:514 [inline] bpf_prog_run_generic_xdp+0x679/0x14c0 net/core/dev.c:4962 netif_receive_generic_xdp net/core/dev.c:5075 [inline] do_xdp_generic+0x673/0xb90 net/core/dev.c:5134 tun_get_user+0x2805/0x4560 drivers/net/tun.c:1924 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: 0033:0x7f806d71bfd0 Code: 40 00 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d d1 e0 07 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89 RSP: 002b:00007fff9b41b6b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fff9b41b750 RCX: 00007f806d71bfd0 RDX: 000000000000fdef RSI: 0000000020000100 RDI: 00000000000000c8 RBP: 00007fff9b41b700 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:bpf_net_ctx_get_ri include/linux/filter.h:788 [inline] RIP: 0010:____bpf_xdp_redirect net/core/filter.c:4561 [inline] RIP: 0010:bpf_xdp_redirect+0x59/0x1a0 net/core/filter.c:4559 Code: 81 c3 00 18 00 00 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 b5 18 90 f8 48 8b 1b 4c 8d 63 38 4c 89 e5 48 c1 ed 03 <42> 0f b6 44 2d 00 84 c0 0f 85 d0 00 00 00 45 8b 34 24 44 89 f6 83 RSP: 0018:ffffc900033bf6f8 EFLAGS: 00010202 RAX: 1ffff11004549e40 RBX: 0000000000000000 RCX: ffff888022a4da00 RDX: 0000000000000000 RSI: 0000000002000000 RDI: ffffc900033bf900 RBP: 0000000000000007 R08: ffffffff895fff80 R09: 1ffff110172a8938 R10: dffffc0000000000 R11: ffffed10172a8939 R12: 0000000000000038 R13: dffffc0000000000 R14: 1ffff92000677f21 R15: 0000000002000000 FS: 000055557e4d4380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000f000 CR3: 000000007abc8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 81 c3 00 18 00 00 add $0x1800,%ebx 6: 48 89 d8 mov %rbx,%rax 9: 48 c1 e8 03 shr $0x3,%rax d: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 12: 74 08 je 0x1c 14: 48 89 df mov %rbx,%rdi 17: e8 b5 18 90 f8 call 0xf89018d1 1c: 48 8b 1b mov (%rbx),%rbx 1f: 4c 8d 63 38 lea 0x38(%rbx),%r12 23: 4c 89 e5 mov %r12,%rbp 26: 48 c1 ed 03 shr $0x3,%rbp * 2a: 42 0f b6 44 2d 00 movzbl 0x0(%rbp,%r13,1),%eax <-- trapping instruction 30: 84 c0 test %al,%al 32: 0f 85 d0 00 00 00 jne 0x108 38: 45 8b 34 24 mov (%r12),%r14d 3c: 44 89 f6 mov %r14d,%esi 3f: 83 .byte 0x83 --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.
