================================================================== BUG: KASAN: slab-use-after-free in rose_get_neigh+0x391/0x990 net/rose/rose_route.c:692 Read of size 1 at addr ffff88805a1cc830 by task syz.2.514/7478 CPU: 0 UID: 0 PID: 7478 Comm: syz.2.514 Not tainted 6.16.0-rc2-syzkaller-00622-g091d019adce0 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 rose_get_neigh+0x391/0x990 net/rose/rose_route.c:692 rose_connect+0x416/0x10a0 net/rose/af_rose.c:816 __sys_connect_file net/socket.c:2084 [inline] __sys_connect+0x316/0x440 net/socket.c:2103 __do_sys_connect net/socket.c:2109 [inline] __se_sys_connect net/socket.c:2106 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2106 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2685b8e929 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:00007f26869f2038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f2685db5fa0 RCX: 00007f2685b8e929 RDX: 000000000000001c RSI: 0000200000000040 RDI: 000000000000000a RBP: 00007f2685c10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2685db5fa0 R15: 00007ffe5a64cd58 Allocated by task 6069: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359 kmalloc_noprof include/linux/slab.h:905 [inline] rose_add_node+0x23a/0xde0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa48/0xfb0 net/rose/rose_route.c:747 rose_ioctl+0x3ce/0x8b0 net/rose/af_rose.c:1380 sock_do_ioctl+0xdc/0x300 net/socket.c:1236 sock_ioctl+0x576/0x790 net/socket.c:1357 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 7478: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 rose_rt_device_down+0x66d/0x6c0 net/rose/rose_route.c:522 rose_device_event+0x603/0x6a0 net/rose/af_rose.c:248 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9565 dev_change_flags+0x130/0x260 net/core/dev_api.c:68 dev_ioctl+0x7b4/0x1150 net/core/dev_ioctl.c:823 sock_do_ioctl+0x22c/0x300 net/socket.c:1250 sock_ioctl+0x576/0x790 net/socket.c:1357 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805a1cc800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 48 bytes inside of freed 512-byte region [ffff88805a1cc800, ffff88805a1cca00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805a1cf400 pfn:0x5a1cc head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801a441c80 ffffea0001626e10 ffffea0001438710 raw: ffff88805a1cf400 000000000010000f 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801a441c80 ffffea0001626e10 ffffea0001438710 head: ffff88805a1cf400 000000000010000f 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001687301 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 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 5206, tgid 5206 (udevd), ts 54501036192, free_ts 46069102907 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4354 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] kernfs_fop_open+0x397/0xca0 fs/kernfs/file.c:623 do_dentry_open+0xdf3/0x1970 fs/open.c:964 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3896 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4055 do_filp_open+0x1fa/0x410 fs/namei.c:4082 do_sys_openat2+0x121/0x1c0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5211 tgid 5211 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 __slab_free+0x326/0x400 mm/slub.c:4554 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204 getname_flags+0xb8/0x540 fs/namei.c:146 do_readlinkat+0xbc/0x500 fs/stat.c:575 __do_sys_readlink fs/stat.c:613 [inline] __se_sys_readlink fs/stat.c:610 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:610 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805a1cc700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805a1cc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805a1cc800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805a1cc880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805a1cc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================