Hello, syzbot found the following issue on: HEAD commit: 3e92c1e6cd87 Merge tag 'selinux-pr-20240402' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=135dbd3d180000 kernel config: https://syzkaller.appspot.com/x/.config?x=5112b3f484393436 dashboard link: https://syzkaller.appspot.com/bug?extid=b6f07e1c07ef40199081 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/ac287f716705/disk-3e92c1e6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f04f8cb0bdc6/vmlinux-3e92c1e6.xz kernel image: https://storage.googleapis.com/syzbot-assets/a8eb9003da40/bzImage-3e92c1e6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+b6f07e1c07ef40199081@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in nf_flow_skb_encap_protocol net/netfilter/nf_flow_table_ip.c:290 [inline] BUG: KMSAN: uninit-value in nf_flow_offload_lookup net/netfilter/nf_flow_table_ip.c:352 [inline] BUG: KMSAN: uninit-value in nf_flow_offload_ip_hook+0x79a/0x3e40 net/netfilter/nf_flow_table_ip.c:424 nf_flow_skb_encap_protocol net/netfilter/nf_flow_table_ip.c:290 [inline] nf_flow_offload_lookup net/netfilter/nf_flow_table_ip.c:352 [inline] nf_flow_offload_ip_hook+0x79a/0x3e40 net/netfilter/nf_flow_table_ip.c:424 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf2/0x3f0 net/netfilter/core.c:626 nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline] nf_ingress net/core/dev.c:5318 [inline] __netif_receive_skb_core+0x430b/0x6190 net/core/dev.c:5406 __netif_receive_skb_one_core net/core/dev.c:5536 [inline] __netif_receive_skb+0xca/0xa00 net/core/dev.c:5652 netif_receive_skb_internal net/core/dev.c:5738 [inline] netif_receive_skb+0x58/0x660 net/core/dev.c:5798 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1549 tun_get_user+0x5566/0x69e0 drivers/net/tun.c:2002 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048 call_write_iter include/linux/fs.h:2108 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xb63/0x1520 fs/read_write.c:590 ksys_write+0x20f/0x4c0 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0x93/0xe0 fs/read_write.c:652 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x72/0x7a Uninit was created at: __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598 alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264 alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335 skb_page_frag_refill+0x2bf/0x7c0 net/core/sock.c:2921 tun_build_skb drivers/net/tun.c:1679 [inline] tun_get_user+0x1258/0x69e0 drivers/net/tun.c:1819 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048 call_write_iter include/linux/fs.h:2108 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xb63/0x1520 fs/read_write.c:590 ksys_write+0x20f/0x4c0 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0x93/0xe0 fs/read_write.c:652 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x72/0x7a CPU: 0 PID: 5636 Comm: syz-executor.0 Not tainted 6.9.0-rc2-syzkaller-00042-g3e92c1e6cd87 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 ===================================================== --- 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
