================================================================== BUG: KASAN: slab-out-of-bounds in fib6_add_rt2node net/ipv6/ip6_fib.c:1140 [inline] BUG: KASAN: slab-out-of-bounds in fib6_add+0x4680/0x46e0 net/ipv6/ip6_fib.c:1503 Read of size 1 at addr ffff88814b99edce by task syz.1.2847/14344 CPU: 0 PID: 14344 Comm: syz.1.2847 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 fib6_add_rt2node net/ipv6/ip6_fib.c:1140 [inline] fib6_add+0x4680/0x46e0 net/ipv6/ip6_fib.c:1503 __ip6_ins_rt net/ipv6/route.c:1352 [inline] ip6_route_add+0x8a/0x160 net/ipv6/route.c:3903 inet6_rtm_newroute+0x2ba/0x1c90 net/ipv6/route.c:5567 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6472 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2da6d9c629 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2da7ce6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f2da7015fa0 RCX: 00007f2da6d9c629 RDX: 0000000000000080 RSI: 0000200000000080 RDI: 0000000000000004 RBP: 00007f2da6e32b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2da7016038 R14: 00007f2da7015fa0 R15: 00007ffd3b58d7b8 Allocated by task 6170: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc+0xb4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x44f/0x1240 net/ipv6/route.c:3803 ip6_route_add+0x28/0x160 net/ipv6/route.c:3899 inet6_rtm_newroute+0x2ba/0x1c90 net/ipv6/route.c:5567 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6472 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x128/0x1f0 kernel/workqueue.c:1835 queue_work include/linux/workqueue.h:562 [inline] call_usermodehelper_exec+0x284/0x4b0 kernel/umh.c:434 kobject_uevent_env+0x681/0x8b0 lib/kobject_uevent.c:633 version_sysfs_builtin+0x8b/0xd0 kernel/params.c:879 param_sysfs_builtin_init+0x28/0x30 kernel/params.c:987 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 kernel_init+0x1d/0x1c0 init/main.c:1455 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88814b99ed00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 22 bytes to the right of allocated 184-byte region [ffff88814b99ed00, ffff88814b99edb8) The buggy address belongs to the physical page: page:ffffea00052e6780 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88814b99e500 pfn:0x14b99e flags: 0x57ff00000000800(slab|node=1|zone=2|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 057ff00000000800 ffff888017c41a00 ffffea00050ad290 ffffea00052e3e50 raw: ffff88814b99e500 0000000000100002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 12661870201, free_ts 11020273611 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4486 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2120 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] call_usermodehelper_setup+0x8e/0x260 kernel/umh.c:363 call_modprobe kernel/module/kmod.c:98 [inline] __request_module+0x3bb/0x600 kernel/module/kmod.c:173 lowpan_module_init+0x57/0xa0 net/6lowpan/core.c:164 do_one_initcall+0x242/0x790 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3ed/0x580 init/main.c:1565 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 vfree+0x1a6/0x320 mm/vmalloc.c:2868 tpg_free+0x52/0x420 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:193 vivid_dev_release+0xb9/0x120 drivers/media/test-drivers/vivid/vivid-core.c:837 v4l2_device_release drivers/media/v4l2-core/v4l2-device.c:51 [inline] kref_put include/linux/kref.h:65 [inline] v4l2_device_put+0x7b/0xc0 drivers/media/v4l2-core/v4l2-device.c:56 vivid_create_instance drivers/media/test-drivers/vivid/vivid-core.c:1979 [inline] vivid_probe+0x409d/0x5c80 drivers/media/test-drivers/vivid/vivid-core.c:2004 platform_probe+0x13b/0x1c0 drivers/base/platform.c:1404 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb20 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __driver_attach+0x44e/0x6e0 drivers/base/dd.c:1216 bus_for_each_dev+0x235/0x2b0 drivers/base/bus.c:370 bus_add_driver+0x340/0x630 drivers/base/bus.c:675 driver_register+0x23a/0x310 drivers/base/driver.c:246 vivid_init+0x3d/0x70 drivers/media/test-drivers/vivid/vivid-core.c:2131 Memory state around the buggy address: ffff88814b99ec80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88814b99ed00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88814b99ed80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ^ ffff88814b99ee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88814b99ee80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================