[v6.1] KASAN: use-after-free Read in ax25_find_cb
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syzbot
Nov 9, 2025, 8:50:27 AM (12 days ago) Nov 9
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: f6e38ae624cf Linux 6.1.158
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=112f1412580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7eb38bd5021fec61
dashboard link: https://syzkaller.appspot.com/bug?extid=3697ea2bf224eb4637cd
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=165c1a58580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2b7003e2661d/disk-f6e38ae6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0696cea8d016/vmlinux-f6e38ae6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6b7a89e636d7/bzImage-f6e38ae6.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3697ea...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in ax25_find_cb+0x175/0x3a0 net/ax25/af_ax25.c:236
Read of size 8 at addr ffff88802fe5f410 by task syz.1.111/4853
CPU: 1 PID: 4853 Comm: syz.1.111 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:420
kasan_report+0x10b/0x140 mm/kasan/report.c:524
ax25_find_cb+0x175/0x3a0 net/ax25/af_ax25.c:236
rose_link_up net/rose/rose_link.c:129 [inline]
rose_transmit_link+0x169/0x730 net/rose/rose_link.c:271
rose_write_internal+0x1096/0x1eb0 net/rose/rose_subr.c:198
rose_release+0x20f/0x4c0 net/rose/af_rose.c:671
__sock_release net/socket.c:654 [inline]
sock_close+0xd5/0x240 net/socket.c:1400
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
get_signal+0x11a6/0x1350 kernel/signal.c:2648
arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1abb38f6c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1abc2cf038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffe00 RBX: 00007f1abb5e6090 RCX: 00007f1abb38f6c9
RDX: 0000000000000040 RSI: 0000200000000100 RDI: 000000000000000a
RBP: 00007f1abb411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1abb5e6128 R14: 00007f1abb5e6090 R15: 00007ffea04c3218
</TASK>
Allocated by task 4764:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383
kmalloc include/linux/slab.h:563 [inline]
kzalloc include/linux/slab.h:699 [inline]
ax25_dev_device_up+0x50/0x5f0 net/ax25/ax25_dev.c:57
ax25_device_event+0x117/0x600 net/ax25/af_ax25.c:143
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
dev_ifsioc+0x159/0xe90 net/core/dev_ioctl.c:327
dev_ioctl+0x578/0xea0 net/core/dev_ioctl.c:588
sock_do_ioctl+0x222/0x2f0 net/socket.c:1218
sock_ioctl+0x4ed/0x6e0 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 4388:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1729 [inline]
slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
slab_free mm/slub.c:3687 [inline]
kmem_cache_free_bulk+0x348/0x460 mm/slub.c:3805
kfree_bulk include/linux/slab.h:475 [inline]
kfree_rcu_work+0x33f/0x890 kernel/rcu/tree.c:3091
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
kvfree_call_rcu+0x108/0x870 kernel/rcu/tree.c:3405
ax25_device_event+0x555/0x600 net/ax25/af_ax25.c:148
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
dev_ifsioc+0x159/0xe90 net/core/dev_ioctl.c:327
dev_ioctl+0x578/0xea0 net/core/dev_ioctl.c:588
sock_do_ioctl+0x222/0x2f0 net/socket.c:1218
sock_ioctl+0x4ed/0x6e0 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Second to last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
call_rcu+0x154/0x980 kernel/rcu/tree.c:2849
fib_create_info+0x1871/0x2490 net/ipv4/fib_semantics.c:1591
fib_table_insert+0xc3/0x1b50 net/ipv4/fib_trie.c:1217
fib_magic+0x2c1/0x390 net/ipv4/fib_frontend.c:1118
fib_add_ifaddr+0x140/0x5e0 net/ipv4/fib_frontend.c:1140
fib_netdev_event+0x361/0x470 net/ipv4/fib_frontend.c:1500
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
do_setlink+0xc31/0x3c40 net/core/rtnetlink.c:2833
__rtnl_newlink net/core/rtnetlink.c:3608 [inline]
rtnl_newlink+0x17d6/0x1ff0 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x79b/0xed0 net/core/rtnetlink.c:6150
netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2511
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x44f/0x5c0 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2161
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff88802fe5f400
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 16 bytes inside of
256-byte region [ffff88802fe5f400, ffff88802fe5f500)
The buggy address belongs to the physical page:
page:ffffea0000bf9780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2fe5e
head:ffffea0000bf9780 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001f82f00 dead000000000005 ffff888017441b40
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4390, tgid 4390 (syz-executor), ts 91386382630, free_ts 76310022183
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
prep_new_page mm/page_alloc.c:2539 [inline]
get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
__alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614
alloc_slab_page+0x5d/0x160 mm/slub.c:1799
allocate_slab mm/slub.c:1944 [inline]
new_slab+0x87/0x2c0 mm/slub.c:1997
___slab_alloc+0xbc6/0x1230 mm/slub.c:3154
__slab_alloc mm/slub.c:3240 [inline]
slab_alloc_node mm/slub.c:3325 [inline]
__kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
__do_kmalloc_node mm/slab_common.c:935 [inline]
__kmalloc+0xa0/0x240 mm/slab_common.c:949
kmalloc include/linux/slab.h:568 [inline]
kzalloc include/linux/slab.h:699 [inline]
fib_create_info+0xa53/0x2490 net/ipv4/fib_semantics.c:1459
fib_table_insert+0xc3/0x1b50 net/ipv4/fib_trie.c:1217
fib_magic+0x2c1/0x390 net/ipv4/fib_frontend.c:1118
fib_add_ifaddr+0x140/0x5e0 net/ipv4/fib_frontend.c:1140
fib_netdev_event+0x361/0x470 net/ipv4/fib_frontend.c:1500
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1459 [inline]
free_pcp_prepare mm/page_alloc.c:1509 [inline]
free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
kmem_cache_zalloc include/linux/slab.h:689 [inline]
journal_alloc_journal_head fs/jbd2/journal.c:2876 [inline]
jbd2_journal_add_journal_head+0x91/0x4c0 fs/jbd2/journal.c:2945
jbd2_journal_get_create_access+0x49/0x440 fs/jbd2/transaction.c:1279
__ext4_journal_get_create_access+0xa2/0x550 fs/ext4/ext4_jbd2.c:330
ext4_getblk+0x45d/0x6d0 fs/ext4/inode.c:917
ext4_bread+0x26/0x170 fs/ext4/inode.c:946
ext4_append+0x2c3/0x560 fs/ext4/namei.c:83
ext4_init_new_dir+0x2b8/0x570 fs/ext4/namei.c:3030
ext4_mkdir+0x47d/0xc50 fs/ext4/namei.c:3076
vfs_mkdir+0x387/0x570 fs/namei.c:4114
Memory state around the buggy address:
ffff88802fe5f300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802fe5f380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802fe5f400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802fe5f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802fe5f500: fc fc fc fc fc fc fc fc 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 syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
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If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want syzbot to run the reproducer, reply with:
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If you attach or paste a git patch, syzbot will apply it before testing.
If you want to overwrite report's subsystems, reply with:
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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
syzbot found the following issue on:
HEAD commit: f6e38ae624cf Linux 6.1.158
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=112f1412580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7eb38bd5021fec61
dashboard link: https://syzkaller.appspot.com/bug?extid=3697ea2bf224eb4637cd
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=165c1a58580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2b7003e2661d/disk-f6e38ae6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0696cea8d016/vmlinux-f6e38ae6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6b7a89e636d7/bzImage-f6e38ae6.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3697ea...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in ax25_find_cb+0x175/0x3a0 net/ax25/af_ax25.c:236
Read of size 8 at addr ffff88802fe5f410 by task syz.1.111/4853
CPU: 1 PID: 4853 Comm: syz.1.111 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:420
kasan_report+0x10b/0x140 mm/kasan/report.c:524
ax25_find_cb+0x175/0x3a0 net/ax25/af_ax25.c:236
rose_link_up net/rose/rose_link.c:129 [inline]
rose_transmit_link+0x169/0x730 net/rose/rose_link.c:271
rose_write_internal+0x1096/0x1eb0 net/rose/rose_subr.c:198
rose_release+0x20f/0x4c0 net/rose/af_rose.c:671
__sock_release net/socket.c:654 [inline]
sock_close+0xd5/0x240 net/socket.c:1400
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
get_signal+0x11a6/0x1350 kernel/signal.c:2648
arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1abb38f6c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1abc2cf038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffe00 RBX: 00007f1abb5e6090 RCX: 00007f1abb38f6c9
RDX: 0000000000000040 RSI: 0000200000000100 RDI: 000000000000000a
RBP: 00007f1abb411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1abb5e6128 R14: 00007f1abb5e6090 R15: 00007ffea04c3218
</TASK>
Allocated by task 4764:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383
kmalloc include/linux/slab.h:563 [inline]
kzalloc include/linux/slab.h:699 [inline]
ax25_dev_device_up+0x50/0x5f0 net/ax25/ax25_dev.c:57
ax25_device_event+0x117/0x600 net/ax25/af_ax25.c:143
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
dev_ifsioc+0x159/0xe90 net/core/dev_ioctl.c:327
dev_ioctl+0x578/0xea0 net/core/dev_ioctl.c:588
sock_do_ioctl+0x222/0x2f0 net/socket.c:1218
sock_ioctl+0x4ed/0x6e0 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 4388:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1729 [inline]
slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
slab_free mm/slub.c:3687 [inline]
kmem_cache_free_bulk+0x348/0x460 mm/slub.c:3805
kfree_bulk include/linux/slab.h:475 [inline]
kfree_rcu_work+0x33f/0x890 kernel/rcu/tree.c:3091
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
kvfree_call_rcu+0x108/0x870 kernel/rcu/tree.c:3405
ax25_device_event+0x555/0x600 net/ax25/af_ax25.c:148
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
dev_ifsioc+0x159/0xe90 net/core/dev_ioctl.c:327
dev_ioctl+0x578/0xea0 net/core/dev_ioctl.c:588
sock_do_ioctl+0x222/0x2f0 net/socket.c:1218
sock_ioctl+0x4ed/0x6e0 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Second to last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
call_rcu+0x154/0x980 kernel/rcu/tree.c:2849
fib_create_info+0x1871/0x2490 net/ipv4/fib_semantics.c:1591
fib_table_insert+0xc3/0x1b50 net/ipv4/fib_trie.c:1217
fib_magic+0x2c1/0x390 net/ipv4/fib_frontend.c:1118
fib_add_ifaddr+0x140/0x5e0 net/ipv4/fib_frontend.c:1140
fib_netdev_event+0x361/0x470 net/ipv4/fib_frontend.c:1500
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
do_setlink+0xc31/0x3c40 net/core/rtnetlink.c:2833
__rtnl_newlink net/core/rtnetlink.c:3608 [inline]
rtnl_newlink+0x17d6/0x1ff0 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x79b/0xed0 net/core/rtnetlink.c:6150
netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2511
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x44f/0x5c0 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2161
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff88802fe5f400
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 16 bytes inside of
256-byte region [ffff88802fe5f400, ffff88802fe5f500)
The buggy address belongs to the physical page:
page:ffffea0000bf9780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2fe5e
head:ffffea0000bf9780 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001f82f00 dead000000000005 ffff888017441b40
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4390, tgid 4390 (syz-executor), ts 91386382630, free_ts 76310022183
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
prep_new_page mm/page_alloc.c:2539 [inline]
get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
__alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614
alloc_slab_page+0x5d/0x160 mm/slub.c:1799
allocate_slab mm/slub.c:1944 [inline]
new_slab+0x87/0x2c0 mm/slub.c:1997
___slab_alloc+0xbc6/0x1230 mm/slub.c:3154
__slab_alloc mm/slub.c:3240 [inline]
slab_alloc_node mm/slub.c:3325 [inline]
__kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
__do_kmalloc_node mm/slab_common.c:935 [inline]
__kmalloc+0xa0/0x240 mm/slab_common.c:949
kmalloc include/linux/slab.h:568 [inline]
kzalloc include/linux/slab.h:699 [inline]
fib_create_info+0xa53/0x2490 net/ipv4/fib_semantics.c:1459
fib_table_insert+0xc3/0x1b50 net/ipv4/fib_trie.c:1217
fib_magic+0x2c1/0x390 net/ipv4/fib_frontend.c:1118
fib_add_ifaddr+0x140/0x5e0 net/ipv4/fib_frontend.c:1140
fib_netdev_event+0x361/0x470 net/ipv4/fib_frontend.c:1500
notifier_call_chain kernel/notifier.c:87 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
call_netdevice_notifiers_extack net/core/dev.c:2039 [inline]
call_netdevice_notifiers net/core/dev.c:2053 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8714
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1459 [inline]
free_pcp_prepare mm/page_alloc.c:1509 [inline]
free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
kmem_cache_zalloc include/linux/slab.h:689 [inline]
journal_alloc_journal_head fs/jbd2/journal.c:2876 [inline]
jbd2_journal_add_journal_head+0x91/0x4c0 fs/jbd2/journal.c:2945
jbd2_journal_get_create_access+0x49/0x440 fs/jbd2/transaction.c:1279
__ext4_journal_get_create_access+0xa2/0x550 fs/ext4/ext4_jbd2.c:330
ext4_getblk+0x45d/0x6d0 fs/ext4/inode.c:917
ext4_bread+0x26/0x170 fs/ext4/inode.c:946
ext4_append+0x2c3/0x560 fs/ext4/namei.c:83
ext4_init_new_dir+0x2b8/0x570 fs/ext4/namei.c:3030
ext4_mkdir+0x47d/0xc50 fs/ext4/namei.c:3076
vfs_mkdir+0x387/0x570 fs/namei.c:4114
Memory state around the buggy address:
ffff88802fe5f300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802fe5f380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802fe5f400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802fe5f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802fe5f500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
---
This report is generated by a bot. It may contain errors.
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