Hello, syzbot found the following issue on: HEAD commit: 2e1b3cc9d7f7 Merge tag 'arm-fixes-6.12-2' of git://git.ker.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=105e0d87980000 kernel config: https://syzkaller.appspot.com/x/.config?x=6fdf74cce377223b dashboard link: https://syzkaller.appspot.com/bug?extid=6023ea32e206eef7920a 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=165d5d5f980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=145e0d87980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/08456e37db58/disk-2e1b3cc9.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/cc957f7ba80b/vmlinux-2e1b3cc9.xz kernel image: https://storage.googleapis.com/syzbot-assets/7579fe72ed89/bzImage-2e1b3cc9.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6023ea32e206eef7920a@xxxxxxxxxxxxxxxxxxxxxxxxx ===================================================== BUG: KMSAN: uninit-value in ip6t_mangle_out net/ipv6/netfilter/ip6table_mangle.c:56 [inline] BUG: KMSAN: uninit-value in ip6table_mangle_hook+0x97d/0x9c0 net/ipv6/netfilter/ip6table_mangle.c:72 ip6t_mangle_out net/ipv6/netfilter/ip6table_mangle.c:56 [inline] ip6table_mangle_hook+0x97d/0x9c0 net/ipv6/netfilter/ip6table_mangle.c:72 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] __ip6_local_out+0x5ac/0x640 net/ipv6/output_core.c:143 ip6_local_out+0x4c/0x210 net/ipv6/output_core.c:153 ip6tunnel_xmit+0x129/0x460 include/net/ip6_tunnel.h:161 ip6_tnl_xmit+0x341a/0x3860 net/ipv6/ip6_tunnel.c:1281 __gre6_xmit+0x14b9/0x1550 net/ipv6/ip6_gre.c:815 ip6gre_xmit_ipv4 net/ipv6/ip6_gre.c:839 [inline] ip6gre_tunnel_xmit+0x18f7/0x2030 net/ipv6/ip6_gre.c:922 __netdev_start_xmit include/linux/netdevice.h:4928 [inline] netdev_start_xmit include/linux/netdevice.h:4937 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3604 sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:3825 [inline] __dev_queue_xmit+0x2fcf/0x56d0 net/core/dev.c:4398 dev_queue_xmit include/linux/netdevice.h:3094 [inline] packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3145 [inline] packet_sendmsg+0x908b/0xa370 net/packet/af_packet.c:3177 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:744 __sys_sendto+0x645/0x7f0 net/socket.c:2214 __do_sys_sendto net/socket.c:2226 [inline] __se_sys_sendto net/socket.c:2222 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2222 x64_sys_call+0x3373/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: ip6_tnl_xmit+0x34f7/0x3860 net/ipv6/ip6_tunnel.c:1277 __gre6_xmit+0x14b9/0x1550 net/ipv6/ip6_gre.c:815 ip6gre_xmit_ipv4 net/ipv6/ip6_gre.c:839 [inline] ip6gre_tunnel_xmit+0x18f7/0x2030 net/ipv6/ip6_gre.c:922 __netdev_start_xmit include/linux/netdevice.h:4928 [inline] netdev_start_xmit include/linux/netdevice.h:4937 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3604 sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:3825 [inline] __dev_queue_xmit+0x2fcf/0x56d0 net/core/dev.c:4398 dev_queue_xmit include/linux/netdevice.h:3094 [inline] packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3145 [inline] packet_sendmsg+0x908b/0xa370 net/packet/af_packet.c:3177 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:744 __sys_sendto+0x645/0x7f0 net/socket.c:2214 __do_sys_sendto net/socket.c:2226 [inline] __se_sys_sendto net/socket.c:2222 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2222 x64_sys_call+0x3373/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4091 [inline] slab_alloc_node mm/slub.c:4134 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_node_track_caller_noprof+0x6c7/0xf90 mm/slub.c:4283 kmalloc_reserve+0x23e/0x4a0 net/core/skbuff.c:609 pskb_expand_head+0x226/0x1a60 net/core/skbuff.c:2275 skb_realloc_headroom+0x140/0x2b0 net/core/skbuff.c:2355 ip6_tnl_xmit+0x2106/0x3860 net/ipv6/ip6_tunnel.c:1227 __gre6_xmit+0x14b9/0x1550 net/ipv6/ip6_gre.c:815 ip6gre_xmit_ipv4 net/ipv6/ip6_gre.c:839 [inline] ip6gre_tunnel_xmit+0x18f7/0x2030 net/ipv6/ip6_gre.c:922 __netdev_start_xmit include/linux/netdevice.h:4928 [inline] netdev_start_xmit include/linux/netdevice.h:4937 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3604 sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:3825 [inline] __dev_queue_xmit+0x2fcf/0x56d0 net/core/dev.c:4398 dev_queue_xmit include/linux/netdevice.h:3094 [inline] packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3145 [inline] packet_sendmsg+0x908b/0xa370 net/packet/af_packet.c:3177 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:744 __sys_sendto+0x645/0x7f0 net/socket.c:2214 __do_sys_sendto net/socket.c:2226 [inline] __se_sys_sendto net/socket.c:2222 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2222 x64_sys_call+0x3373/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 1 UID: 0 PID: 5819 Comm: syz-executor359 Not tainted 6.12.0-rc6-syzkaller-00077-g2e1b3cc9d7f7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 ===================================================== --- This report is generated by a bot. 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