BUG: KASAN: use-after-free in llc_conn_ac_send_sabme_cmd_p_set_x+0x332/0x3c0 net/llc/llc_c_ac.c:788 Read of size 1 at addr ffff88801c25b010 by task ksoftirqd/0/14 CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 llc_conn_ac_send_sabme_cmd_p_set_x+0x332/0x3c0 net/llc/llc_c_ac.c:788 llc_exec_conn_trans_actions net/llc/llc_conn.c:442 [inline] llc_conn_service net/llc/llc_conn.c:367 [inline] llc_conn_state_process+0x506/0x12b0 net/llc/llc_conn.c:71 llc_process_tmr_ev net/llc/llc_c_ac.c:1445 [inline] llc_conn_tmr_common_cb+0x336/0x7e0 net/llc/llc_c_ac.c:1331 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648 expire_timers kernel/time/timer.c:1699 [inline] __run_timers+0x56c/0x810 kernel/time/timer.c:1970 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983 handle_softirqs+0x336/0x830 kernel/softirq.c:576 run_ksoftirqd+0xa4/0x100 kernel/softirq.c:943 smpboot_thread_fn+0x520/0x990 kernel/smpboot.c:164 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 6734: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] llc_sap_alloc net/llc/llc_core.c:35 [inline] llc_sap_open+0xda/0x330 net/llc/llc_core.c:102 llc_ui_autobind+0x1fa/0x4b0 net/llc/af_llc.c:306 llc_ui_connect+0x1c5/0xc70 net/llc/af_llc.c:501 __sys_connect_file net/socket.c:1933 [inline] __sys_connect+0x3cb/0x450 net/socket.c:1950 __do_sys_connect net/socket.c:1960 [inline] __se_sys_connect net/socket.c:1957 [inline] __x64_sys_connect+0x76/0x80 net/socket.c:1957 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 Freed by task 1106: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free_bulk+0x38b/0x490 mm/slub.c:3645 kfree_bulk include/linux/slab.h:465 [inline] kfree_rcu_work+0x311/0x900 kernel/rcu/tree.c:3299 process_one_work+0x867/0xff0 kernel/workqueue.c:2310 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 kvfree_call_rcu+0x105/0x7f0 kernel/rcu/tree.c:3600 llc_sap_put include/net/llc.h:132 [inline] llc_ui_release+0x212/0x450 net/llc/af_llc.c:223 __sock_release net/socket.c:651 [inline] sock_close+0xbf/0x210 net/socket.c:1346 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 get_signal+0x123e/0x12e0 kernel/signal.c:2681 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88801c25b000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 16 bytes inside of 2048-byte region [ffff88801c25b000, ffff88801c25b800) The buggy address belongs to the page: page:ffffea0000709600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c258 head:ffffea0000709600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888016c42000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 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 1, ts 3520783333, free_ts 0 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2031 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc_trace+0xf9/0x290 mm/slub.c:3250 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] acpi_os_allocate_zeroed include/acpi/platform/aclinuxex.h:57 [inline] acpi_ds_create_walk_state+0xe2/0x270 drivers/acpi/acpica/dswstate.c:518 acpi_ps_execute_method+0x21d/0x7a0 drivers/acpi/acpica/psxface.c:134 acpi_ns_evaluate+0x661/0xa30 drivers/acpi/acpica/nseval.c:205 acpi_ut_evaluate_object+0x12f/0x480 drivers/acpi/acpica/uteval.c:60 acpi_ut_execute_STA+0x44/0x130 drivers/acpi/acpica/uteval.c:223 acpi_ns_get_device_callback+0x210/0x4b0 drivers/acpi/acpica/nsxfeval.c:723 acpi_ns_walk_namespace+0x21f/0x6a0 drivers/acpi/acpica/nswalk.c:-1 acpi_get_devices+0x108/0x170 drivers/acpi/acpica/nsxfeval.c:805 pnpacpi_init+0x7e/0x120 drivers/pnp/pnpacpi/core.c:308 do_one_initcall+0x272/0x730 init/main.c:1315 page_owner free stack trace missing Memory state around the buggy address: ffff88801c25af00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801c25af80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801c25b000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801c25b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801c25b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================