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KASAN: slab-use-after-free Read in ax25_send_frame (2)

Status: closed as invalid on 2026/03/27 01:43
Subsystems: hams
[Documentation on labels]
First crash: 41d, last: 3d05h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
090eb30c-788f-44a9-8cc8-dffd603786c6 repro KASAN: slab-use-after-free Read in ax25_send_frame (2) 2026/03/08 01:21 2026/03/08 01:21 2026/03/08 01:30 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in ax25_send_frame hams 19 1 157d 157d 0/29 auto-obsoleted due to no activity on 2025/12/31 09:06
upstream general protection fault in ax25_send_frame (2) hams 10 13 1239d 1225d 22/29 fixed on 2023/02/24 13:50

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in ax25_send_frame+0xae6/0xb70 net/ax25/ax25_out.c:75
Read of size 7 at addr ffff88807bf30008 by task syz.3.800/10037

CPU: 1 UID: 0 PID: 10037 Comm: syz.3.800 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 ax25_send_frame+0xae6/0xb70 net/ax25/ax25_out.c:75
 rose_send_frame+0xfa/0x2a0 net/rose/rose_link.c:106
 rose_transmit_restart_request+0x1b8/0x250 net/rose/rose_link.c:198
 rose_t0timer_expiry+0x1d/0x150 net/rose/rose_link.c:83
 call_timer_fn+0x19a/0x670 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb30 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 76 91 55 f6 48 89 df e8 5e e1 55 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 f5 17 46 f6 65 8b 05 3e 7e 7d 08 85 c0 74 16 5b
RSP: 0018:ffffc90004877758 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff888078ed0100 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffffff8de756c6 RDI: ffffffff8c1acf20
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888022351780
R13: 0000000000000246 R14: ffff888078ed00e8 R15: ffffc900048778d8
 spin_unlock_irqrestore include/linux/spinlock.h:407 [inline]
 __skb_try_recv_datagram+0x16a/0x500 net/core/datagram.c:267
 __unix_dgram_recvmsg+0x1bc/0xc30 net/unix/af_unix.c:2571
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2670
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 ____sys_recvmsg+0x5f7/0x6b0 net/socket.c:2810
 ___sys_recvmsg+0x16a/0x1a0 net/socket.c:2854
 do_recvmmsg+0x301/0x760 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f67ddf9bf79
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:00007f67dc1f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f67de216090 RCX: 00007f67ddf9bf79
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f67de0327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f67de216128 R14: 00007f67de216090 R15: 00007fff6aa916e8
 </TASK>

Allocated by task 8446:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kmalloc_noprof include/linux/slab.h:962 [inline]
 rose_add_node net/rose/rose_route.c:85 [inline]
 rose_rt_ioctl+0x586/0x2550 net/rose/rose_route.c:748
 rose_ioctl+0x491/0x7d0 net/rose/af_rose.c:1382
 sock_do_ioctl+0x118/0x280 net/socket.c:1254
 sock_ioctl+0x599/0x6b0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10040:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2670 [inline]
 slab_free mm/slub.c:6082 [inline]
 kfree+0x1f6/0x6b0 mm/slub.c:6399
 rose_neigh_put include/net/rose.h:166 [inline]
 rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183
 call_timer_fn+0x19a/0x670 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb30 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

The buggy address belongs to the object at ffff88807bf30000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 freed 512-byte region [ffff88807bf30000, ffff88807bf30200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807bf32400 pfn:0x7bf30
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88813fe37c80 ffffea0001ed9210 ffffea0000d59610
raw: ffff88807bf32400 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe37c80 ffffea0001ed9210 ffffea0000d59610
head: ffff88807bf32400 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0001efcc01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5189, tgid 5189 (udevadm), ts 31690501388, free_ts 26345350699
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1888
 prep_new_page mm/page_alloc.c:1896 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249
 alloc_slab_page mm/slub.c:3238 [inline]
 allocate_slab mm/slub.c:3411 [inline]
 new_slab+0xa6/0x6e0 mm/slub.c:3469
 refill_objects+0x26b/0x400 mm/slub.c:7091
 refill_sheaf mm/slub.c:2787 [inline]
 alloc_full_sheaf mm/slub.c:2808 [inline]
 __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4546
 alloc_from_pcs mm/slub.c:4639 [inline]
 slab_alloc_node mm/slub.c:4773 [inline]
 __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5292
 kmalloc_noprof include/linux/slab.h:962 [inline]
 kzalloc_noprof include/linux/slab.h:1204 [inline]
 kernfs_fop_open+0x23d/0xd50 fs/kernfs/file.c:641
 do_dentry_open+0x6d8/0x1660 fs/open.c:949
 vfs_open+0x82/0x3f0 fs/open.c:1081
 do_open fs/namei.c:4671 [inline]
 path_openat+0x208c/0x31a0 fs/namei.c:4830
 do_file_open+0x20e/0x430 fs/namei.c:4859
 do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1432 [inline]
 __free_frozen_pages+0x7ca/0x10a0 mm/page_alloc.c:2977
 __free_pages mm/page_alloc.c:5368 [inline]
 free_contig_range+0xde/0x1d0 mm/page_alloc.c:7372
 debug_vm_pgtable_free_huge_page mm/debug_vm_pgtable.c:980 [inline]
 destroy_args+0xa8/0x7a0 mm/debug_vm_pgtable.c:993
 debug_vm_pgtable+0x1b66/0x34c0 mm/debug_vm_pgtable.c:1368
 do_one_initcall+0x11d/0x760 init/main.c:1382
 do_initcall_level init/main.c:1444 [inline]
 do_initcalls init/main.c:1460 [inline]
 do_basic_setup init/main.c:1479 [inline]
 kernel_init_freeable+0x6e5/0x7a0 init/main.c:1692
 kernel_init+0x1f/0x1e0 init/main.c:1582
 ret_from_fork+0x754/0xd80 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:
 ffff88807bf2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807bf2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807bf30000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88807bf30080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807bf30100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in kmemdup_noprof+0x44/0x60 mm/util.c:140
Read of size 66 at addr ffff888022aed600 by task syz.3.800/10037

CPU: 1 UID: 0 PID: 10037 Comm: syz.3.800 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:186 [inline]
 kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 kmemdup_noprof+0x44/0x60 mm/util.c:140
 kmemdup_noprof include/linux/fortify-string.h:763 [inline]
 ax25_send_frame+0x414/0xb70 net/ax25/ax25_out.c:78
 rose_send_frame+0xfa/0x2a0 net/rose/rose_link.c:106
 rose_transmit_restart_request+0x1b8/0x250 net/rose/rose_link.c:198
 rose_t0timer_expiry+0x1d/0x150 net/rose/rose_link.c:83
 call_timer_fn+0x19a/0x670 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb30 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 76 91 55 f6 48 89 df e8 5e e1 55 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 f5 17 46 f6 65 8b 05 3e 7e 7d 08 85 c0 74 16 5b
RSP: 0018:ffffc90004877758 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff888078ed0100 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffffff8de756c6 RDI: ffffffff8c1acf20
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888022351780
R13: 0000000000000246 R14: ffff888078ed00e8 R15: ffffc900048778d8
 spin_unlock_irqrestore include/linux/spinlock.h:407 [inline]
 __skb_try_recv_datagram+0x16a/0x500 net/core/datagram.c:267
 __unix_dgram_recvmsg+0x1bc/0xc30 net/unix/af_unix.c:2571
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2670
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 ____sys_recvmsg+0x5f7/0x6b0 net/socket.c:2810
 ___sys_recvmsg+0x16a/0x1a0 net/socket.c:2854
 do_recvmmsg+0x301/0x760 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f67ddf9bf79
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:00007f67dc1f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f67de216090 RCX: 00007f67ddf9bf79
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f67de0327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f67de216128 R14: 00007f67de216090 R15: 00007fff6aa916e8
 </TASK>

Allocated by task 8446:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kmalloc_noprof include/linux/slab.h:962 [inline]
 rose_add_node net/rose/rose_route.c:109 [inline]
 rose_rt_ioctl+0x1bd8/0x2550 net/rose/rose_route.c:748
 rose_ioctl+0x491/0x7d0 net/rose/af_rose.c:1382
 sock_do_ioctl+0x118/0x280 net/socket.c:1254
 sock_ioctl+0x599/0x6b0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10040:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2670 [inline]
 slab_free mm/slub.c:6082 [inline]
 kfree+0x1f6/0x6b0 mm/slub.c:6399
 rose_neigh_put include/net/rose.h:165 [inline]
 rose_timer_expiry+0x537/0x630 net/rose/rose_timer.c:183
 call_timer_fn+0x19a/0x670 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb30 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

The buggy address belongs to the object at ffff888022aed600
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 0 bytes inside of
 freed 96-byte region [ffff888022aed600, ffff888022aed660)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888022aedf00 pfn:0x22aed
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88813fe37280 ffffea0000da7950 ffffea0000bf4d50
raw: ffff888022aedf00 0000000000200019 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 1, tgid 1 (swapper/0), ts 3110598489, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1888
 prep_new_page mm/page_alloc.c:1896 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249
 alloc_slab_page mm/slub.c:3238 [inline]
 allocate_slab mm/slub.c:3411 [inline]
 new_slab+0xa6/0x6e0 mm/slub.c:3469
 refill_objects+0x26b/0x400 mm/slub.c:7091
 refill_sheaf mm/slub.c:2787 [inline]
 alloc_full_sheaf mm/slub.c:2808 [inline]
 __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4546
 alloc_from_pcs mm/slub.c:4639 [inline]
 slab_alloc_node mm/slub.c:4773 [inline]
 __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5292
 kmalloc_noprof include/linux/slab.h:962 [inline]
 kzalloc_noprof include/linux/slab.h:1204 [inline]
 class_dir_create_and_add drivers/base/core.c:3223 [inline]
 get_device_parent+0x29a/0x4c0 drivers/base/core.c:3283
 device_add+0x1ad/0x1950 drivers/base/core.c:3613
 wakeup_source_device_create+0x243/0x2e0 drivers/base/power/wakeup_stats.c:163
 wakeup_source_sysfs_add+0x1c/0x90 drivers/base/power/wakeup_stats.c:183
 wakeup_source_register+0x154/0x3e0 drivers/base/power/wakeup.c:218
 acpi_add_pm_notifier+0x123/0x270 drivers/acpi/device_pm.c:589
 pci_acpi_add_pm_notifier drivers/pci/pci-acpi.c:891 [inline]
 pci_acpi_setup+0x268/0x6f0 drivers/pci/pci-acpi.c:1441
 acpi_device_notify+0x283/0x500 drivers/acpi/glue.c:381
 device_platform_notify drivers/base/core.c:2377 [inline]
 device_add+0x2b4/0x1950 drivers/base/core.c:3634
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888022aed500: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
 ffff888022aed580: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff888022aed600: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                   ^
 ffff888022aed680: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
 ffff888022aed700: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in rose_send_frame+0x266/0x2a0 net/rose/rose_link.c:106
Write of size 8 at addr ffff88807bf30018 by task syz.3.800/10037

CPU: 1 UID: 0 PID: 10037 Comm: syz.3.800 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 rose_send_frame+0x266/0x2a0 net/rose/rose_link.c:106
 rose_transmit_restart_request+0x1b8/0x250 net/rose/rose_link.c:198
 rose_t0timer_expiry+0x1d/0x150 net/rose/rose_link.c:83
 call_timer_fn+0x19a/0x670 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb30 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 76 91 55 f6 48 89 df e8 5e e1 55 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 f5 17 46 f6 65 8b 05 3e 7e 7d 08 85 c0 74 16 5b
RSP: 0018:ffffc90004877758 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff888078ed0100 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffffff8de756c6 RDI: ffffffff8c1acf20
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888022351780
R13: 0000000000000246 R14: ffff888078ed00e8 R15: ffffc900048778d8
 spin_unlock_irqrestore include/linux/spinlock.h:407 [inline]
 __skb_try_recv_datagram+0x16a/0x500 net/core/datagram.c:267
 __unix_dgram_recvmsg+0x1bc/0xc30 net/unix/af_unix.c:2571
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2670
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 ____sys_recvmsg+0x5f7/0x6b0 net/socket.c:2810
 ___sys_recvmsg+0x16a/0x1a0 net/socket.c:2854
 do_recvmmsg+0x301/0x760 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f67ddf9bf79
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:00007f67dc1f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f67de216090 RCX: 00007f67ddf9bf79
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f67de0327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f67de216128 R14: 00007f67de216090 R15: 00007fff6aa916e8
 </TASK>

Allocated by task 8446:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kmalloc_noprof include/linux/slab.h:962 [inline]
 rose_add_node net/rose/rose_route.c:85 [inline]
 rose_rt_ioctl+0x586/0x2550 net/rose/rose_route.c:748
 rose_ioctl+0x491/0x7d0 net/rose/af_rose.c:1382
 sock_do_ioctl+0x118/0x280 net/socket.c:1254
 sock_ioctl+0x599/0x6b0 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10040:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2670 [inline]
 slab_free mm/slub.c:6082 [inline]
 kfree+0x1f6/0x6b0 mm/slub.c:6399
 rose_neigh_put include/net/rose.h:166 [inline]
 rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183
 call_timer_fn+0x19a/0x670 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb30 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

The buggy address belongs to the object at ffff88807bf30000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
 freed 512-byte region [ffff88807bf30000, ffff88807bf30200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807bf32400 pfn:0x7bf30
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88813fe37c80 ffffea0001ed9210 ffffea0000d59610
raw: ffff88807bf32400 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe37c80 ffffea0001ed9210 ffffea0000d59610
head: ffff88807bf32400 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0001efcc01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5189, tgid 5189 (udevadm), ts 31690501388, free_ts 26345350699
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1888
 prep_new_page mm/page_alloc.c:1896 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249
 alloc_slab_page mm/slub.c:3238 [inline]
 allocate_slab mm/slub.c:3411 [inline]
 new_slab+0xa6/0x6e0 mm/slub.c:3469
 refill_objects+0x26b/0x400 mm/slub.c:7091
 refill_sheaf mm/slub.c:2787 [inline]
 alloc_full_sheaf mm/slub.c:2808 [inline]
 __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4546
 alloc_from_pcs mm/slub.c:4639 [inline]
 slab_alloc_node mm/slub.c:4773 [inline]
 __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5292
 kmalloc_noprof include/linux/slab.h:962 [inline]
 kzalloc_noprof include/linux/slab.h:1204 [inline]
 kernfs_fop_open+0x23d/0xd50 fs/kernfs/file.c:641
 do_dentry_open+0x6d8/0x1660 fs/open.c:949
 vfs_open+0x82/0x3f0 fs/open.c:1081
 do_open fs/namei.c:4671 [inline]
 path_openat+0x208c/0x31a0 fs/namei.c:4830
 do_file_open+0x20e/0x430 fs/namei.c:4859
 do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1432 [inline]
 __free_frozen_pages+0x7ca/0x10a0 mm/page_alloc.c:2977
 __free_pages mm/page_alloc.c:5368 [inline]
 free_contig_range+0xde/0x1d0 mm/page_alloc.c:7372
 debug_vm_pgtable_free_huge_page mm/debug_vm_pgtable.c:980 [inline]
 destroy_args+0xa8/0x7a0 mm/debug_vm_pgtable.c:993
 debug_vm_pgtable+0x1b66/0x34c0 mm/debug_vm_pgtable.c:1368
 do_one_initcall+0x11d/0x760 init/main.c:1382
 do_initcall_level init/main.c:1444 [inline]
 do_initcalls init/main.c:1460 [inline]
 do_basic_setup init/main.c:1479 [inline]
 kernel_init_freeable+0x6e5/0x7a0 init/main.c:1692
 kernel_init+0x1f/0x1e0 init/main.c:1582
 ret_from_fork+0x754/0xd80 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:
 ffff88807bf2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807bf2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807bf30000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88807bf30080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807bf30100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	f5                   	cmc
   1:	53                   	push   %rbx
   2:	48 8b 74 24 10       	mov    0x10(%rsp),%rsi
   7:	48 89 fb             	mov    %rdi,%rbx
   a:	48 83 c7 18          	add    $0x18,%rdi
   e:	e8 76 91 55 f6       	call   0xf6559189
  13:	48 89 df             	mov    %rbx,%rdi
  16:	e8 5e e1 55 f6       	call   0xf655e179
  1b:	f7 c5 00 02 00 00    	test   $0x200,%ebp
  21:	75 23                	jne    0x46
  23:	9c                   	pushf
  24:	58                   	pop    %rax
  25:	f6 c4 02             	test   $0x2,%ah
  28:	75 37                	jne    0x61
* 2a:	bf 01 00 00 00       	mov    $0x1,%edi <-- trapping instruction
  2f:	e8 f5 17 46 f6       	call   0xf6461829
  34:	65 8b 05 3e 7e 7d 08 	mov    %gs:0x87d7e3e(%rip),%eax        # 0x87d7e79
  3b:	85 c0                	test   %eax,%eax
  3d:	74 16                	je     0x55
  3f:	5b                   	pop    %rbx

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/14 13:58 upstream 770aaedb461a 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root KASAN: slab-use-after-free Read in ax25_send_frame
2026/03/20 06:40 net 7c770dadfda5 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in ax25_send_frame
2026/03/25 03:47 net-next b1c803d5c816 35e4ff71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in ax25_send_frame
2026/03/13 17:44 net-next 8f921f610054 351cb5cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in ax25_send_frame
2026/03/10 15:32 net-next 89fe91c65992 4683d576 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in ax25_send_frame
2026/03/04 11:18 net-next 4ad96a7c9e2c e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in ax25_send_frame
2026/03/03 21:16 net-next ed0abfe93fd1 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in ax25_send_frame
* Struck through repros no longer work on HEAD.