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=1228a3b9980000 kernel config: https://syzkaller.appspot.com/x/.config?x=ed034204f2e40e53 dashboard link: https://syzkaller.appspot.com/bug?extid=08811615f0e17bc6708b 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=12512bc1980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10fe346e980000 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+08811615f0e17bc6708b@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: 1 UID: 0 PID: 5101 Comm: syz-executor153 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_map include/linux/filter.h:1699 [inline] RIP: 0010:dev_map_redirect+0x65/0x6a0 kernel/bpf/devmap.c:1015 Code: 48 c1 e8 03 80 3c 28 00 74 08 48 89 df e8 83 b3 3d 00 4c 8b 2b 4d 8d 7d 38 4c 89 fb 48 c1 eb 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 03 84 c0 0f 85 6e 04 00 00 41 8b 2f 89 ee 83 e6 02 31 ff RSP: 0018:ffffc9000355f6e8 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000007 RCX: ffff888018b78000 RDX: 0000000000000000 RSI: 000000000355f738 RDI: ffff8880183a2800 RBP: dffffc0000000000 R08: 0000000000000007 R09: ffffffff81b5ee2f R10: 0000000000000004 R11: ffff888018b78000 R12: 000000000355f738 R13: 0000000000000000 R14: 0000000000000008 R15: 0000000000000038 FS: 000055557cbd4380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000f000 CR3: 0000000078ac6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> bpf_prog_ec9efaa32d58ce69+0x56/0x5a __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: 0033:0x7fa9a2adcf90 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 31 e1 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:00007ffd3cd09788 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa9a2adcf90 RDX: 000000000000fdef RSI: 0000000020000100 RDI: 00000000000000c8 RBP: 0000000000000000 R08: 00007ffd3cd098b8 R09: 00007ffd3cd098b8 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_map include/linux/filter.h:1699 [inline] RIP: 0010:dev_map_redirect+0x65/0x6a0 kernel/bpf/devmap.c:1015 Code: 48 c1 e8 03 80 3c 28 00 74 08 48 89 df e8 83 b3 3d 00 4c 8b 2b 4d 8d 7d 38 4c 89 fb 48 c1 eb 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 03 84 c0 0f 85 6e 04 00 00 41 8b 2f 89 ee 83 e6 02 31 ff RSP: 0018:ffffc9000355f6e8 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000007 RCX: ffff888018b78000 RDX: 0000000000000000 RSI: 000000000355f738 RDI: ffff8880183a2800 RBP: dffffc0000000000 R08: 0000000000000007 R09: ffffffff81b5ee2f R10: 0000000000000004 R11: ffff888018b78000 R12: 000000000355f738 R13: 0000000000000000 R14: 0000000000000008 R15: 0000000000000038 FS: 000055557cbd4380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000f000 CR3: 0000000078ac6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 c1 e8 03 shr $0x3,%rax 4: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) 8: 74 08 je 0x12 a: 48 89 df mov %rbx,%rdi d: e8 83 b3 3d 00 call 0x3db395 12: 4c 8b 2b mov (%rbx),%r13 15: 4d 8d 7d 38 lea 0x38(%r13),%r15 19: 4c 89 fb mov %r15,%rbx 1c: 48 c1 eb 03 shr $0x3,%rbx 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df * 2a: 0f b6 04 03 movzbl (%rbx,%rax,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 6e 04 00 00 jne 0x4a4 36: 41 8b 2f mov (%r15),%ebp 39: 89 ee mov %ebp,%esi 3b: 83 e6 02 and $0x2,%esi 3e: 31 ff xor %edi,%edi --- 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.
