syzbot has found a reproducer for the following issue on: HEAD commit: 7846b618e0a4 Merge tag 'rtc-6.11' of git://git.kernel.org/.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=142d3eb5980000 kernel config: https://syzkaller.appspot.com/x/.config?x=be4129de17851dbe dashboard link: https://syzkaller.appspot.com/bug?extid=44623300f057a28baf1e compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=154c40b1980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14f3e11d980000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-7846b618.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/3a2831ffe61c/vmlinux-7846b618.xz kernel image: https://storage.googleapis.com/syzbot-assets/575e23a7c452/bzImage-7846b618.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+44623300f057a28baf1e@xxxxxxxxxxxxxxxxxxxxxxxxx Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 5389 Comm: syz-executor357 Not tainted 6.10.0-syzkaller-11323-g7846b618e0a4 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:__dev_flush+0x49/0x1e0 kernel/bpf/devmap.c:424 Code: 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 98 01 00 00 48 b8 00 00 00 00 00 fc ff df 49 8b 2f 48 8d 5d 80 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 69 01 00 00 48 8b 45 00 49 39 ef 4c 8d 60 80 0f RSP: 0018:ffffc900008b0c90 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffffffffffffff80 RCX: ffffffff88d6a5bb RDX: 0000000000000000 RSI: ffffffff81af9c56 RDI: ffffc9000345fa68 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc9000345fa58 R13: ffff888022ec0fb0 R14: ffffc9000345fa68 R15: ffffc9000345fa68 FS: 0000555568ea6380(0000) GS:ffff88806b100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff4743880f0 CR3: 0000000023168000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> xdp_do_check_flushed+0x40a/0x4e0 net/core/filter.c:4300 __napi_poll.constprop.0+0xd1/0x550 net/core/dev.c:6774 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0xa92/0x1010 net/core/dev.c:6962 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 </IRQ> <TASK> __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] tun_get_user+0x1d9b/0x3c30 drivers/net/tun.c:1936 tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2052 new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6b6/0x1140 fs/read_write.c:590 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff47430af50 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 51 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:00007ffde0326728 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffde03267c0 RCX: 00007ff47430af50 RDX: 0000000000000e80 RSI: 0000000020000100 RDI: 00000000000000c8 RBP: 00007ffde0326770 R08: 00007ffde0326750 R09: 00007ffde0326750 R10: 00007ffde0326750 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__dev_flush+0x49/0x1e0 kernel/bpf/devmap.c:424 Code: 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 98 01 00 00 48 b8 00 00 00 00 00 fc ff df 49 8b 2f 48 8d 5d 80 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 69 01 00 00 48 8b 45 00 49 39 ef 4c 8d 60 80 0f RSP: 0018:ffffc900008b0c90 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffffffffffffff80 RCX: ffffffff88d6a5bb RDX: 0000000000000000 RSI: ffffffff81af9c56 RDI: ffffc9000345fa68 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc9000345fa58 R13: ffff888022ec0fb0 R14: ffffc9000345fa68 R15: ffffc9000345fa68 FS: 0000555568ea6380(0000) GS:ffff88806b100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff4743880f0 CR3: 0000000023168000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 48 c1 ea 03 shr $0x3,%rdx 4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 8: 0f 85 98 01 00 00 jne 0x1a6 e: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 15: fc ff df 18: 49 8b 2f mov (%r15),%rbp 1b: 48 8d 5d 80 lea -0x80(%rbp),%rbx 1f: 48 89 ea mov %rbp,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx * 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2a: 0f 85 69 01 00 00 jne 0x199 30: 48 8b 45 00 mov 0x0(%rbp),%rax 34: 49 39 ef cmp %rbp,%r15 37: 4c 8d 60 80 lea -0x80(%rax),%r12 3b: 0f .byte 0xf --- 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.
