Hello, syzbot found the following issue on:
HEAD commit: b85966adbf5d Merge tag 'net-next-7.2' of git://git.kernel... git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=16d3e3a1580000 kernel config: https://syzkaller.appspot.com/x/.config?x=9a9f723a32776544 dashboard link: https://syzkaller.appspot.com/bug?extid=4707bb8a43a42fca2b97 compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d65306d96573/disk-b85966ad.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ef43139aab0e/vmlinux-b85966ad.xz kernel image: https://storage.googleapis.com/syzbot-assets/26d4d1ab67c3/bzImage-b85966ad.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: [email protected] netdevsim netdevsim0 netdevsim0: left allmulticast mode 8021q: adding VLAN 0 to HW filter on device netdevsim0 8021q: adding VLAN 0 to HW filter on device netdevsim1 8021q: adding VLAN 0 to HW filter on device netdevsim2 8021q: adding VLAN 0 to HW filter on device netdevsim3 ================================================================== BUG: KASAN: slab-use-after-free in hwsim_set_promiscuous_mode+0x2b4/0x2e0 drivers/net/ieee802154/mac802154_hwsim.c:323 Read of size 1 at addr ffff88802adb1800 by task syz.0.303/7013 CPU: 1 UID: 0 PID: 7013 Comm: syz.0.303 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: <TASK> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 hwsim_set_promiscuous_mode+0x2b4/0x2e0 drivers/net/ieee802154/mac802154_hwsim.c:323 drv_set_promiscuous_mode+0x159/0x2e0 net/mac802154/driver-ops.h:127 drv_start net/mac802154/driver-ops.h:195 [inline] mac802154_slave_open net/mac802154/iface.c:196 [inline] mac802154_wpan_open+0x196e/0x29f0 net/mac802154/iface.c:295 __dev_open+0x46f/0x850 net/core/dev.c:1702 __dev_change_flags+0x329/0x820 net/core/dev.c:9754 netif_change_flags+0x7c/0x1b0 net/core/dev.c:9817 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3207 rtnl_group_changelink net/core/rtnetlink.c:3855 [inline] __rtnl_newlink net/core/rtnetlink.c:4023 [inline] rtnl_newlink+0x148e/0x1bd0 net/core/rtnetlink.c:4151 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7068 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738 __sys_sendmsg net/socket.c:2770 [inline] __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff94f19ce59 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:00007ff9500a3028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ff94f416090 RCX: 00007ff94f19ce59 RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000008 RBP: 00007ff94f232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff94f416128 R14: 00007ff94f416090 R15: 00007ffcb835f4f8 </TASK> Allocated by task 5605: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x318/0x660 mm/slub.c:5451 _kmalloc_noprof include/linux/slab.h:969 [inline] _kzalloc_noprof include/linux/slab.h:1286 [inline] hwsim_update_pib+0x88/0x450 drivers/net/ieee802154/mac802154_hwsim.c:101 hwsim_set_promiscuous_mode+0x196/0x2e0 drivers/net/ieee802154/mac802154_hwsim.c:323 drv_set_promiscuous_mode+0x159/0x2e0 net/mac802154/driver-ops.h:127 drv_start net/mac802154/driver-ops.h:195 [inline] mac802154_slave_open net/mac802154/iface.c:196 [inline] mac802154_wpan_open+0x196e/0x29f0 net/mac802154/iface.c:295 __dev_open+0x46f/0x850 net/core/dev.c:1702 __dev_change_flags+0x329/0x820 net/core/dev.c:9754 netif_change_flags+0x7c/0x1b0 net/core/dev.c:9817 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3207 rtnl_changelink net/core/rtnetlink.c:3841 [inline] __rtnl_newlink net/core/rtnetlink.c:4014 [inline] rtnl_newlink+0x15c2/0x1bd0 net/core/rtnetlink.c:4151 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7068 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x626/0x6c0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2255 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 23: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2700 [inline] __rcu_free_sheaf_prepare+0x12d/0x2a0 mm/slub.c:2951 rcu_free_sheaf+0x31/0x200 mm/slub.c:5909 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897 handle_softirqs+0x225/0x840 kernel/softirq.c:622 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1076 smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88802adb1800 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 0 bytes inside of freed 64-byte region [ffff88802adb1800, ffff88802adb1840) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2adb1 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88813fe1b8c0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800200020 00000000f5000000 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 12, tgid 12 (kworker/u8:0), ts 8480159325, free_ts 7414718607 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x24ae/0x2530 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3289 [inline] allocate_slab+0x74/0x5d0 mm/slub.c:3404 new_slab mm/slub.c:3447 [inline] refill_objects+0x328/0x3c0 mm/slub.c:7241 refill_sheaf mm/slub.c:2827 [inline] __pcs_replace_empty_main+0x2e0/0x6b0 mm/slub.c:4692 alloc_from_pcs mm/slub.c:4790 [inline] slab_alloc_node mm/slub.c:4924 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_noprof+0x464/0x750 mm/slub.c:5347 _kmalloc_noprof include/linux/slab.h:973 [inline] _kzalloc_noprof include/linux/slab.h:1286 [inline] lsm_blob_alloc security/security.c:218 [inline] lsm_task_alloc security/security.c:270 [inline] security_task_alloc+0x4d/0x330 security/security.c:2785 copy_process+0x1c57/0x42e0 kernel/fork.c:2269 kernel_clone+0x2d7/0x940 kernel/fork.c:2745 user_mode_thread+0x110/0x180 kernel/fork.c:2821 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:171 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 page last free pid 10 tgid 10 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0xc0d/0xd20 mm/page_alloc.c:2938 vfree+0x1fd/0x330 mm/vmalloc.c:3472 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:3392 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88802adb1700: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802adb1780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88802adb1800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff88802adb1880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802adb1900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== --- 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 [email protected]. 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
