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KASAN: use-after-free Read in ax25_release

Status: upstream: reported on 2025/02/26 18:03
Reported-by: syzbot+38f5235bade356590c03@syzkaller.appspotmail.com
First crash: 233d, last: 20h06m
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in ax25_release hams 19 8 270d 291d 0/29 auto-obsoleted due to no activity on 2025/04/30 05:50

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in ax25_release+0x5ca/0x870 net/ax25/af_ax25.c:1061
Read of size 8 at addr ffff888024c63e08 by task syz.3.351/5472

CPU: 1 PID: 5472 Comm: syz.3.351 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 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
 ax25_release+0x5ca/0x870 net/ax25/af_ax25.c:1061
 __sock_release net/socket.c:649 [inline]
 sock_close+0xd5/0x240 net/socket.c:1336
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 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
RIP: 0033:0x7fd36ec95ec9
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:00007ffe81382c98 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fd36eeeeda0 RCX: 00007fd36ec95ec9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fd36eeeeda0 R08: 00000000000000c0 R09: 0000000a81382f8f
R10: 00000000003ffd1c R11: 0000000000000246 R12: 0000000000022e0a
R13: 00007ffe81382d90 R14: ffffffffffffffff R15: 00007ffe81382db0
 </TASK>

Allocated by task 4959:
 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+0xb5/0xf0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:604 [inline]
 kzalloc include/linux/slab.h:735 [inline]
 ax25_dev_device_up+0x50/0x580 net/ax25/ax25_dev.c:55
 ax25_device_event+0x483/0x4f0 net/ax25/af_ax25.c:139
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline]
 call_netdevice_notifiers net/core/dev.c:2075 [inline]
 __dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929
 dev_ifsioc+0x147/0xe70 net/core/dev_ioctl.c:324
 dev_ioctl+0x55f/0xe50 net/core/dev_ioctl.c:587
 sock_do_ioctl+0x222/0x2f0 net/socket.c:1154
 sock_ioctl+0x4ed/0x6e0 net/socket.c:1257
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 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 5474:
 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+0xea/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 ax25_device_event+0x4b4/0x4f0 net/ax25/af_ax25.c:144
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline]
 call_netdevice_notifiers net/core/dev.c:2075 [inline]
 __dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929
 dev_ifsioc+0x147/0xe70 net/core/dev_ioctl.c:324
 dev_ioctl+0x55f/0xe50 net/core/dev_ioctl.c:587
 sock_do_ioctl+0x222/0x2f0 net/socket.c:1154
 sock_ioctl+0x4ed/0x6e0 net/socket.c:1257
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 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

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
 insert_work+0x54/0x3d0 kernel/workqueue.c:1366
 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532
 queue_work_on+0x11d/0x1d0 kernel/workqueue.c:1559
 inet6addr_event+0x9c/0xc0 drivers/infiniband/core/roce_gid_mgmt.c:883
 notifier_call_chain kernel/notifier.c:83 [inline]
 atomic_notifier_call_chain+0x15d/0x280 kernel/notifier.c:198
 ipv6_add_addr+0xb30/0xde0 net/ipv6/addrconf.c:1182
 inet6_addr_add+0x43a/0x9c0 net/ipv6/addrconf.c:2998
 inet6_rtm_newaddr+0x5d7/0x840 net/ipv6/addrconf.c:4951
 rtnetlink_rcv_msg+0x9b9/0xe60 net/core/rtnetlink.c:5650
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 __sys_sendto+0x423/0x580 net/socket.c:2063
 __do_sys_sendto net/socket.c:2075 [inline]
 __se_sys_sendto net/socket.c:2071 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2071
 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

The buggy address belongs to the object at ffff888024c63e00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 8 bytes inside of
 192-byte region [ffff888024c63e00, ffff888024c63ec0)
The buggy address belongs to the page:
page:ffffea00009318c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888024c63b00 pfn:0x24c63
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea00008fcf88 ffffea00008c5fc8 ffff888016841a00
raw: ffff888024c63b00 000000000010000c 00000001ffffffff 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 0x12c00(GFP_NOIO|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 11935274640, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
 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+0x81e/0xdf0 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]
 __kmalloc+0x1cd/0x330 mm/slub.c:4408
 kmalloc include/linux/slab.h:609 [inline]
 usb_alloc_urb+0x3f/0x140 drivers/usb/core/urb.c:74
 usb_internal_control_msg drivers/usb/core/message.c:95 [inline]
 usb_control_msg+0x115/0x3e0 drivers/usb/core/message.c:153
 set_port_feature drivers/usb/core/hub.c:455 [inline]
 hub_suspend+0x769/0x970 drivers/usb/core/hub.c:3912
 usb_suspend_interface drivers/usb/core/driver.c:1307 [inline]
 usb_suspend_both+0x28a/0x1050 drivers/usb/core/driver.c:1412
 usb_runtime_suspend+0x54/0x100 drivers/usb/core/driver.c:1950
 __rpm_callback+0x2eb/0x7e0 drivers/base/power/runtime.c:395
 rpm_callback drivers/base/power/runtime.c:532 [inline]
 rpm_suspend+0x87a/0x1a50 drivers/base/power/runtime.c:672
 __pm_runtime_suspend+0x10f/0x150 drivers/base/power/runtime.c:1108
 pm_runtime_put_sync_autosuspend include/linux/pm_runtime.h:508 [inline]
 usb_new_device+0xeab/0x1640 drivers/usb/core/hub.c:2662
 register_root_hub+0x278/0x580 drivers/usb/core/hcd.c:1021
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888024c63d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888024c63d80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff888024c63e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888024c63e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888024c63f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (273):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/17 03:53 linux-5.15.y 29e53a5b1c4f 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/10/16 19:41 linux-5.15.y 29e53a5b1c4f 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/10/11 01:08 linux-5.15.y 29e53a5b1c4f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/10/06 20:19 linux-5.15.y 29e53a5b1c4f 91305dbe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/10/06 07:00 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/10/05 13:17 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/28 05:22 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/27 03:38 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/27 03:37 linux-5.15.y 43bb85222e53 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/26 18:14 linux-5.15.y 43bb85222e53 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/26 07:15 linux-5.15.y 43bb85222e53 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/23 04:20 linux-5.15.y 43bb85222e53 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/21 21:50 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/21 19:20 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/21 14:28 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/21 03:44 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/20 22:09 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/20 11:46 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/18 23:49 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/18 13:14 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/17 17:25 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/14 09:13 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/11 15:54 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/09/11 09:18 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/28 12:50 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/28 09:51 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/28 01:21 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/27 03:23 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/23 19:17 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/17 02:38 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/15 17:17 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/15 11:19 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/11 03:04 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/10 12:44 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/02/26 18:02 linux-5.15.y c16c81c81336 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_release
2025/08/28 02:19 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/28 00:06 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/27 04:30 linux-5.15.y c79648372d02 e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/24 00:52 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/22 12:31 linux-5.15.y c79648372d02 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/17 12:01 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/16 02:46 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/12 15:28 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/12 06:39 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
2025/08/10 01:35 linux-5.15.y c79648372d02 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_release
* Struck through repros no longer work on HEAD.