================================================================== BUG: KASAN: use-after-free in ifname_compare_aligned include/linux/netfilter/x_tables.h:412 [inline] BUG: KASAN: use-after-free in ip_packet_match net/ipv4/netfilter/ip_tables.c:64 [inline] BUG: KASAN: use-after-free in ipt_do_table+0x6d8/0x1590 net/ipv4/netfilter/ip_tables.c:284 Read of size 8 at addr ffff888128794000 by task syz.2.290/1435 CPU: 1 PID: 1435 Comm: syz.2.290 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 ifname_compare_aligned include/linux/netfilter/x_tables.h:412 [inline] ip_packet_match net/ipv4/netfilter/ip_tables.c:64 [inline] ipt_do_table+0x6d8/0x1590 net/ipv4/netfilter/ip_tables.c:284 iptable_mangle_hook+0x196/0x4d0 net/ipv4/netfilter/iptable_mangle.c:79 nf_hook_entry_hookfn include/linux/netfilter.h:143 [inline] nf_hook_slow+0xbc/0x200 net/netfilter/core.c:590 nf_hook include/linux/netfilter.h:260 [inline] NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip_mc_output+0x5a3/0x7e0 net/ipv4/ip_output.c:415 dst_output include/net/dst.h:453 [inline] ip_local_out net/ipv4/ip_output.c:126 [inline] ip_send_skb+0xb2/0x140 net/ipv4/ip_output.c:1581 udp_send_skb+0x938/0x1240 net/ipv4/udp.c:991 udp_sendmsg+0x173d/0x20b0 net/ipv4/udp.c:1279 inet_sendmsg+0xa5/0xc0 net/ipv4/af_inet.c:830 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490 __sys_sendmmsg+0x278/0x480 net/socket.c:2576 __do_sys_sendmmsg net/socket.c:2605 [inline] __se_sys_sendmmsg net/socket.c:2602 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2602 x64_sys_call+0x6c6/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f590cc56ec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f590b69e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f590ceae090 RCX: 00007f590cc56ec9 RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000006 RBP: 00007f590ccd9f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f590ceae128 R14: 00007f590ceae090 R15: 00007ffd1a8e2fd8 The buggy address belongs to the page: page:ffffea0004a1e500 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x128794 flags: 0x4000000000000000(zone=1) raw: 4000000000000000 ffffea0004452f08 ffff8881f713c5f0 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 2, migratetype Unmovable, gfp_mask 0x446dc0(GFP_KERNEL_ACCOUNT|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP|__GFP_ZERO), pid 285, ts 24704205624, free_ts 96037594617 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5808 __alloc_pages_node include/linux/gfp.h:595 [inline] alloc_pages_node include/linux/gfp.h:609 [inline] alloc_pages include/linux/gfp.h:622 [inline] kmalloc_order+0x4c/0x160 mm/slab_common.c:995 kmalloc_order_trace+0x18/0xb0 mm/slab_common.c:1014 kmalloc_large include/linux/slab.h:545 [inline] __kmalloc+0x199/0x2c0 mm/slub.c:4425 __kmalloc_node include/linux/slab.h:484 [inline] kmalloc_node include/linux/slab.h:639 [inline] kvmalloc_node+0x206/0x300 mm/util.c:621 kvmalloc include/linux/mm.h:862 [inline] kvzalloc include/linux/mm.h:870 [inline] alloc_netdev_mqs+0x8d/0xc90 net/core/dev.c:10900 tun_set_iff+0x535/0xe00 drivers/net/tun.c:2773 __tun_chr_ioctl+0x7e8/0x1eb0 drivers/net/tun.c:3062 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3349 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0x121/0x1a0 fs/ioctl.c:860 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:860 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x6c/0x100 mm/page_alloc.c:5884 free_nonslab_page+0x86/0xc0 mm/slub.c:3564 kfree+0x19a/0x270 mm/slub.c:4585 kvfree+0x35/0x40 mm/util.c:661 netdev_freemem+0x3f/0x60 net/core/dev.c:10854 netdev_release+0x7f/0xb0 net/core/net-sysfs.c:1903 device_release+0x96/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:713 [inline] kobject_release lib/kobject.c:744 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x18a/0x270 lib/kobject.c:761 netdev_run_todo+0x812/0x990 net/core/dev.c:10710 rtnl_unlock net/core/rtnetlink.c:112 [inline] rtnetlink_rcv_msg+0xa1d/0xb90 net/core/rtnetlink.c:5651 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922 Memory state around the buggy address: ffff888128793f00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe ffff888128793f80: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe >ffff888128794000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888128794080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888128794100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================