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KASAN: use-after-free Read in ax25_fillin_cb (2)

Status: upstream: reported C repro on 2024/12/29 08:09
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+cb55d909987f69524941@syzkaller.appspotmail.com
First crash: 113d, last: 8d06h
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/03/14 linux-5.15.y (ToT) 0c935c049b5c C [report] KASAN: use-after-free Read in ax25_fillin_cb
2025/03/14 upstream (ToT) 695caca9345a C Didn't crash
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in ax25_fillin_cb hams syz 4 2308d 2306d 11/28 fixed on 2019/01/15 20:25
linux-5.15 KASAN: use-after-free Read in ax25_fillin_cb 1 291d 291d 0/3 auto-obsoleted due to no activity on 2024/10/12 11:28

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in ax25_fillin_cb_from_dev net/ax25/af_ax25.c:468 [inline]
BUG: KASAN: use-after-free in ax25_fillin_cb+0x460/0x660 net/ax25/af_ax25.c:495
Read of size 4 at addr ffff88801a3c0138 by task syz-executor262/4175

CPU: 0 PID: 4175 Comm: syz-executor262 Not tainted 5.15.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 ax25_fillin_cb_from_dev net/ax25/af_ax25.c:468 [inline]
 ax25_fillin_cb+0x460/0x660 net/ax25/af_ax25.c:495
 ax25_setsockopt+0xab7/0xe70 net/ax25/af_ax25.c:690
 __sys_setsockopt+0x57e/0x990 net/socket.c:2203
 __do_sys_setsockopt net/socket.c:2214 [inline]
 __se_sys_setsockopt net/socket.c:2211 [inline]
 __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2211
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f9d344965d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 31 1a 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffee49f78a8 EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f9d344965d9
RDX: 0000000000000019 RSI: 0000000000000101 RDI: 0000000000000004
RBP: 00007ffee49f78e0 R08: 0000000000000010 R09: 0000000000000001
R10: 0000200000000000 R11: 0000000000000206 R12: 00000000000f4240
R13: 000000000000ed63 R14: 00007ffee49f78c4 R15: 00007ffee49f78d0
 </TASK>

Allocated by task 4172:
 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+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247
 kmalloc include/linux/slab.h:604 [inline]
 kzalloc include/linux/slab.h:735 [inline]
 ax25_dev_device_up+0x51/0x5a0 net/ax25/ax25_dev.c:55
 ax25_device_event+0x4a0/0x510 net/ax25/af_ax25.c:139
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:391
 __dev_notify_flags+0x1fd/0x3f0 net/core/dev.c:-1
 dev_change_flags+0xe7/0x190 net/core/dev.c:8928
 dev_ifsioc+0x147/0x10c0 net/core/dev_ioctl.c:324
 dev_ioctl+0x504/0xf60 net/core/dev_ioctl.c:587
 sock_do_ioctl+0x34f/0x5a0 net/socket.c:1154
 sock_ioctl+0x484/0x770 net/socket.c:1257
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 4174:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 ax25_dev_put include/net/ax25.h:302 [inline]
 ax25_release+0x3b3/0x840 net/ax25/af_ax25.c:1062
 __sock_release net/socket.c:649 [inline]
 sock_close+0xcd/0x230 net/socket.c:1336
 __fput+0x3fe/0x8e0 fs/file_table.c:311
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88801a3c0100
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 56 bytes inside of
 192-byte region [ffff88801a3c0100, ffff88801a3c01c0)
The buggy address belongs to the page:
page:ffffea000068f000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1a3c0
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 dead000000000100 dead000000000122 ffff888017441a00
raw: 0000000000000000 0000000000100010 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 2311389386, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5466
 alloc_page_interleave+0x22/0x1c0 mm/mempolicy.c:2031
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 __kmalloc_track_caller+0x1c7/0x300 mm/slub.c:4925
 __do_krealloc mm/slab_common.c:1244 [inline]
 krealloc+0x5c/0xf0 mm/slab_common.c:1277
 add_sysfs_param+0xca/0x7f0 kernel/params.c:651
 kernel_add_sysfs_param+0xb0/0x130 kernel/params.c:812
 param_sysfs_builtin+0x16a/0x1f0 kernel/params.c:851
 param_sysfs_init+0x66/0x70 kernel/params.c:970
 do_one_initcall+0x22b/0x7a0 init/main.c:1302
 do_initcall_level+0x157/0x210 init/main.c:1375
 do_initcalls+0x49/0x90 init/main.c:1391
 kernel_init_freeable+0x425/0x5c0 init/main.c:1615
 kernel_init+0x19/0x290 init/main.c:1506
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88801a3c0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801a3c0080: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88801a3c0100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88801a3c0180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88801a3c0200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (49):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/13 19:22 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/13 16:45 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/13 14:59 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/13 11:41 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/09 02:56 linux-5.15.y 0c935c049b5c a775275d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/23 22:07 linux-5.15.y 0c935c049b5c 4e8d3850 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/03 17:24 linux-5.15.y c16c81c81336 c3901742 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/02 08:16 linux-5.15.y c16c81c81336 c3901742 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/02 08:12 linux-5.15.y c16c81c81336 c3901742 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 06:34 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 05:46 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 04:56 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/02/28 10:33 linux-5.15.y c16c81c81336 6a8fcbc4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/02/28 09:48 linux-5.15.y c16c81c81336 6a8fcbc4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/02/26 20:14 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/02/26 19:30 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/02/26 18:45 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/13 14:12 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/04/13 10:50 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/04/13 09:51 linux-5.15.y f7347f400572 0bd6db41 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/04/02 23:48 linux-5.15.y 0c935c049b5c c799dfdd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/08 03:34 linux-5.15.y c16c81c81336 7e3bd60d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/08 02:33 linux-5.15.y c16c81c81336 7e3bd60d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/08 01:34 linux-5.15.y c16c81c81336 7e3bd60d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/08 00:44 linux-5.15.y c16c81c81336 7e3bd60d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/05 02:22 linux-5.15.y c16c81c81336 c3901742 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/03 14:58 linux-5.15.y c16c81c81336 c3901742 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 04:16 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 04:15 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 03:05 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/03/01 03:05 linux-5.15.y c16c81c81336 67cf5345 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/02/28 07:07 linux-5.15.y c16c81c81336 6a8fcbc4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/02/28 06:22 linux-5.15.y c16c81c81336 6a8fcbc4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/02/26 19:35 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/02/26 18:50 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 18:58 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 18:58 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:52 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:51 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:49 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:47 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:46 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:44 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/12 12:44 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/03/05 06:01 linux-5.15.y c16c81c81336 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2024/12/29 08:08 linux-5.15.y 91786f140358 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ax25_fillin_cb
2025/04/06 07:13 linux-5.15.y 0c935c049b5c 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
2025/04/06 07:10 linux-5.15.y 0c935c049b5c 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ax25_fillin_cb
* Struck through repros no longer work on HEAD.