================================================================== BUG: KASAN: slab-use-after-free in ax25_release+0x87d/0x950 net/ax25/af_ax25.c:1062 Read of size 1 at addr ffff88807d930ecc by task syz.1.908/8861 CPU: 1 UID: 0 PID: 8861 Comm: syz.1.908 Not tainted 6.13.0-rc5-syzkaller-00172-gd1bf27c4e176 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 ax25_release+0x87d/0x950 net/ax25/af_ax25.c:1062 __sock_release net/socket.c:640 [inline] sock_close+0xbc/0x240 net/socket.c:1408 __fput+0x23c/0xa50 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdc1e585d29 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:00007ffd276cdbc8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fdc1e777ba0 RCX: 00007fdc1e585d29 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fdc1e777ba0 R08: 0000000000000124 R09: 00007ffd276cdebf R10: 00000000003ffcb4 R11: 0000000000000246 R12: 000000000001d4b3 R13: 00007fdc1e776080 R14: 0000000000000032 R15: ffffffffffffffff Allocated by task 8801: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] ax25_dev_device_up+0x58/0x620 net/ax25/ax25_dev.c:57 ax25_device_event+0x4f3/0x580 net/ax25/af_ax25.c:143 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 __dev_notify_flags+0x207/0x400 dev_change_flags+0xf0/0x1a0 net/core/dev.c:9045 dev_ifsioc+0x7c8/0xe70 net/core/dev_ioctl.c:526 dev_ioctl+0x719/0x1340 net/core/dev_ioctl.c:783 sock_do_ioctl+0x240/0x460 net/socket.c:1223 sock_ioctl+0x626/0x8e0 net/socket.c:1328 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8864: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4613 [inline] kfree+0x196/0x430 mm/slub.c:4761 ax25_device_event+0x529/0x580 net/ax25/af_ax25.c:148 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 __dev_notify_flags+0x207/0x400 dev_change_flags+0xf0/0x1a0 net/core/dev.c:9045 dev_ifsioc+0x7c8/0xe70 net/core/dev_ioctl.c:526 dev_ioctl+0x719/0x1340 net/core/dev_ioctl.c:783 sock_do_ioctl+0x240/0x460 net/socket.c:1223 sock_ioctl+0x626/0x8e0 net/socket.c:1328 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807d930e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 204 bytes inside of freed 256-byte region [ffff88807d930e00, ffff88807d930f00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d930 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac41b40 ffffea0001834480 dead000000000004 raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac41b40 ffffea0001834480 dead000000000004 head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 00fff00000000001 ffffea0001f64c01 ffffffffffffffff 0000000000000000 head: 0000000000000002 0000000000000000 00000000ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5827, tgid 5827 (syz-executor), ts 64760027883, free_ts 64754221753 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3476 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269 alloc_slab_page+0x6a/0x110 mm/slub.c:2423 allocate_slab+0x5a/0x2b0 mm/slub.c:2589 new_slab mm/slub.c:2642 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830 __slab_alloc+0x58/0xa0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] ____ip_mc_inc_group+0x5a2/0xe50 net/ipv4/igmp.c:1468 __ip_mc_inc_group net/ipv4/igmp.c:1503 [inline] ip_mc_inc_group net/ipv4/igmp.c:1509 [inline] ip_mc_up+0x124/0x300 net/ipv4/igmp.c:1808 inetdev_event+0xfa4/0x1550 net/ipv4/devinet.c:1638 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 __dev_notify_flags+0x207/0x400 dev_change_flags+0xf0/0x1a0 net/core/dev.c:9045 do_setlink+0xc90/0x4210 net/core/rtnetlink.c:3109 page last free pid 5836 tgid 5836 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2659 discard_slab mm/slub.c:2688 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3157 put_cpu_partial+0x17c/0x250 mm/slub.c:3232 __slab_free+0x290/0x380 mm/slub.c:4483 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] __kmalloc_cache_noprof+0x1d9/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] ____ip_mc_inc_group+0x5a2/0xe50 net/ipv4/igmp.c:1468 __ip_mc_inc_group net/ipv4/igmp.c:1503 [inline] ip_mc_inc_group net/ipv4/igmp.c:1509 [inline] ip_mc_up+0x124/0x300 net/ipv4/igmp.c:1808 inetdev_event+0xfa4/0x1550 net/ipv4/devinet.c:1638 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 __dev_notify_flags+0x207/0x400 dev_change_flags+0xf0/0x1a0 net/core/dev.c:9045 do_setlink+0xc90/0x4210 net/core/rtnetlink.c:3109 rtnl_changelink net/core/rtnetlink.c:3723 [inline] __rtnl_newlink net/core/rtnetlink.c:3875 [inline] rtnl_newlink+0x1bb6/0x2210 net/core/rtnetlink.c:4012 Memory state around the buggy address: ffff88807d930d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807d930e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807d930e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807d930f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807d930f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================