================================================================== BUG: KASAN: use-after-free in rose_transmit_link+0x5b0/0x730 net/rose/rose_link.c:266 Read of size 1 at addr ffff88801ec6b432 by task syz.4.263/5269 CPU: 1 PID: 5269 Comm: syz.4.263 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: 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 rose_transmit_link+0x5b0/0x730 net/rose/rose_link.c:266 rose_write_internal+0x673/0x1e80 net/rose/rose_subr.c:198 rose_release+0x22a/0x4e0 net/rose/af_rose.c:670 __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 get_signal+0x1222/0x12c0 kernel/signal.c:2672 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 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+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: 0033:0x7f084e2e1be9 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:00007f084c528038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffe00 RBX: 00007f084e509090 RCX: 00007f084e2e1be9 RDX: 000000000000001c RSI: 0000200000000240 RDI: 0000000000000009 RBP: 00007f084e364e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f084e509128 R14: 00007f084e509090 R15: 00007ffedfe0d4d8 Allocated by task 4404: 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] rose_add_node+0x227/0xdb0 net/rose/rose_route.c:85 rose_rt_ioctl+0x9db/0xe20 net/rose/rose_route.c:738 rose_ioctl+0x27a/0x790 net/rose/af_rose.c:1372 sock_do_ioctl+0xd3/0x2f0 net/socket.c:1140 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 5263: 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:1705 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xef/0x2a0 mm/slub.c:4559 rose_rt_device_down+0x4e2/0x530 net/rose/rose_route.c:515 rose_device_event+0x5ec/0x680 net/rose/af_rose.c:247 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 The buggy address belongs to the object at ffff88801ec6b400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 50 bytes inside of 512-byte region [ffff88801ec6b400, ffff88801ec6b600) The buggy address belongs to the page: page:ffffea00007b1a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801ec6a400 pfn:0x1ec68 head:ffffea00007b1a00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001815908 ffffea0001816108 ffff888016841c80 raw: ffff88801ec6a400 0000000000100006 00000001ffffffff 0000000000000000 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 3564, ts 24019193800, free_ts 24008270155 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:5474 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1975 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4958 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:290 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast+0x2e6/0x530 lib/kobject_uevent.c:409 kobject_uevent_env+0x556/0x890 lib/kobject_uevent.c:608 kobject_synth_uevent+0x520/0xaf0 lib/kobject_uevent.c:208 store_uevent+0x12/0x20 kernel/module.c:1167 module_attr_store+0x5b/0x80 kernel/params.c:919 kernfs_fop_write_iter+0x379/0x4c0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_write+0x14d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 free_slab mm/slub.c:2015 [inline] discard_slab mm/slub.c:2021 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2507 put_cpu_partial+0x12d/0x190 mm/slub.c:2587 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3233 getname_flags+0xb5/0x500 fs/namei.c:138 do_sys_openat2+0xcf/0x4a0 fs/open.c:1247 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 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 Memory state around the buggy address: ffff88801ec6b300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801ec6b380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801ec6b400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801ec6b480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801ec6b500: fb fb fb fb fb fb fb fb 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