================================================================== BUG: KASAN: slab-use-after-free in handle_tx+0x1ec/0x610 drivers/net/caif/caif_serial.c:222 Read of size 8 at addr ffff88807f15e020 by task aoe_tx0/1304 CPU: 0 UID: 0 PID: 1304 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 handle_tx+0x1ec/0x610 drivers/net/caif/caif_serial.c:222 __netdev_start_xmit include/linux/netdevice.h:5222 [inline] netdev_start_xmit include/linux/netdevice.h:5231 [inline] xmit_one net/core/dev.c:3839 [inline] dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3855 __dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4725 dev_queue_xmit include/linux/netdevice.h:3361 [inline] tx+0x6b/0x190 drivers/block/aoe/aoenet.c:62 kthread+0x1cd/0x3e0 drivers/block/aoe/aoecmd.c:1241 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6171: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x21c/0x3a0 mm/slub.c:4396 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1043 [inline] alloc_tty_struct+0xa6/0x780 drivers/tty/tty_io.c:3102 tty_init_dev+0x59/0x4d0 drivers/tty/tty_io.c:1400 tty_open_by_driver drivers/tty/tty_io.c:2073 [inline] tty_open+0x5ab/0xd10 drivers/tty/tty_io.c:2120 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x950/0x13f0 fs/open.c:965 vfs_open+0x3b/0x340 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5920: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kfree+0x18e/0x440 mm/slub.c:4879 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559 insert_work+0x3d/0x330 kernel/workqueue.c:2184 __queue_work+0xcd2/0xfb0 kernel/workqueue.c:2339 queue_work_on+0x181/0x270 kernel/workqueue.c:2390 tty_release_struct+0xb8/0xd0 drivers/tty/tty_io.c:1692 tty_release+0xcb0/0x1640 drivers/tty/tty_io.c:1852 __fput+0x449/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807f15e000 which belongs to the cache kmalloc-cg-2k of size 2048 The buggy address is located 32 bytes inside of freed 2048-byte region [ffff88807f15e000, ffff88807f15e800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807f158000 pfn:0x7f158 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888032aaae01 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801a84b3c0 ffffea0001fb5e10 ffffea0001588c10 raw: ffff88807f158000 0000000000080006 00000000f5000000 ffff888032aaae01 head: 00fff00000000240 ffff88801a84b3c0 ffffea0001fb5e10 ffffea0001588c10 head: ffff88807f158000 0000000000080006 00000000f5000000 ffff888032aaae01 head: 00fff00000000003 ffffea0001fc5601 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5863, tgid 5863 (syz-executor), ts 76302384156, free_ts 75435415786 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x330 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbd1/0x13e0 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_node_track_caller_noprof+0x2e4/0x4a0 mm/slub.c:4384 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:765 [inline] neigh_sysctl_register+0x9f/0xa80 net/core/neighbour.c:3826 addrconf_sysctl_register+0xb3/0x1c0 net/ipv6/addrconf.c:7365 ipv6_add_dev+0xd46/0x1370 net/ipv6/addrconf.c:460 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11244 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1034 [inline] nsim_create+0xae8/0xf10 drivers/net/netdevsim/netdev.c:1105 __nsim_dev_port_add+0x6b6/0xb10 drivers/net/netdevsim/dev.c:1438 page last free pid 5863 tgid 5863 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x146/0x170 mm/slub.c:3218 put_cpu_partial+0x17c/0x250 mm/slub.c:3293 __slab_free+0x2b9/0x390 mm/slub.c:4550 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] __kmalloc_cache_noprof+0x1aa/0x3a0 mm/slub.c:4391 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1043 [inline] ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271 __netdev_tracker_alloc include/linux/netdevice.h:4349 [inline] netdev_hold include/linux/netdevice.h:4378 [inline] netdev_queue_add_kobject net/core/net-sysfs.c:1992 [inline] netdev_queue_update_kobjects+0x1d1/0x6c0 net/core/net-sysfs.c:2054 register_queue_kobjects net/core/net-sysfs.c:2117 [inline] netdev_register_kobject+0x258/0x310 net/core/net-sysfs.c:2360 register_netdevice+0x126c/0x1ae0 net/core/dev.c:11206 veth_newlink+0x5cc/0xa50 drivers/net/veth.c:1884 rtnl_newlink_create+0x30d/0xb00 net/core/rtnetlink.c:3825 __rtnl_newlink net/core/rtnetlink.c:3942 [inline] rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4057 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6946 Memory state around the buggy address: ffff88807f15df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807f15df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807f15e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807f15e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807f15e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================