================================================================== BUG: KASAN: slab-use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline] BUG: KASAN: slab-use-after-free in rht_head_hashfn include/linux/rhashtable.h:174 [inline] BUG: KASAN: slab-use-after-free in __rhashtable_remove_fast_one include/linux/rhashtable.h:1007 [inline] BUG: KASAN: slab-use-after-free in __rhashtable_remove_fast include/linux/rhashtable.h:1093 [inline] BUG: KASAN: slab-use-after-free in rhashtable_remove_fast include/linux/rhashtable.h:1122 [inline] BUG: KASAN: slab-use-after-free in xfs_buf_rele_cached fs/xfs/xfs_buf.c:923 [inline] BUG: KASAN: slab-use-after-free in xfs_buf_rele+0x950/0xfe0 fs/xfs/xfs_buf.c:948 Read of size 4 at addr ffff88805d8ab408 by task syz.1.222/7235 CPU: 1 UID: 0 PID: 7235 Comm: syz.1.222 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 rht_key_hashfn include/linux/rhashtable.h:159 [inline] rht_head_hashfn include/linux/rhashtable.h:174 [inline] __rhashtable_remove_fast_one include/linux/rhashtable.h:1007 [inline] __rhashtable_remove_fast include/linux/rhashtable.h:1093 [inline] rhashtable_remove_fast include/linux/rhashtable.h:1122 [inline] xfs_buf_rele_cached fs/xfs/xfs_buf.c:923 [inline] xfs_buf_rele+0x950/0xfe0 fs/xfs/xfs_buf.c:948 xfs_buftarg_shrink_scan+0x23e/0x2d0 fs/xfs/xfs_buf.c:1650 do_shrink_slab+0x6ec/0x1110 mm/shrinker.c:437 shrink_slab+0xd74/0x10d0 mm/shrinker.c:664 drop_slab_node mm/vmscan.c:434 [inline] drop_slab+0x14e/0x290 mm/vmscan.c:452 drop_caches_sysctl_handler+0xc7/0x170 fs/drop_caches.c:68 proc_sys_call_handler+0x4c9/0x700 fs/proc/proc_sysctl.c:600 do_iter_readv_writev+0x632/0x8d0 fs/read_write.c:-1 vfs_writev+0x323/0x970 fs/read_write.c:1057 do_writev+0x153/0x2d0 fs/read_write.c:1103 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f722deaeec9 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:00007f722c10e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f722e105fa0 RCX: 00007f722deaeec9 RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000004 RBP: 00007f722df31f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f722e106038 R14: 00007f722e105fa0 R15: 00007fffff47f9b8 Allocated by task 7210: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5604 [inline] __kvmalloc_node_noprof+0x3fd/0x920 mm/slub.c:7044 bucket_table_alloc lib/rhashtable.c:186 [inline] rhashtable_init_noprof+0x506/0xbd0 lib/rhashtable.c:1075 xfs_perag_alloc fs/xfs/libxfs/xfs_ag.c:238 [inline] xfs_initialize_perag+0x284/0x630 fs/xfs/libxfs/xfs_ag.c:279 xfs_mountfs+0xae0/0x22c0 fs/xfs/xfs_mount.c:995 xfs_fs_fill_super+0x1185/0x15d0 fs/xfs/xfs_super.c:1926 get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1691 vfs_get_tree+0x8f/0x2b0 fs/super.c:1751 fc_mount fs/namespace.c:1208 [inline] do_new_mount_fc fs/namespace.c:3651 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3727 do_mount fs/namespace.c:4050 [inline] __do_sys_mount fs/namespace.c:4238 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4215 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5800: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2515 [inline] slab_free mm/slub.c:6574 [inline] kfree+0x197/0x950 mm/slub.c:6781 rhashtable_free_and_destroy+0x7e8/0x940 lib/rhashtable.c:1173 xfs_group_free+0x166/0x370 fs/xfs/libxfs/xfs_group.c:171 xfs_free_perag_range+0x36/0x60 fs/xfs/libxfs/xfs_ag.c:133 xfs_unmountfs+0x2db/0x320 fs/xfs/xfs_mount.c:1360 xfs_fs_put_super+0x65/0x160 fs/xfs/xfs_super.c:1234 generic_shutdown_super+0x132/0x2c0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1722 xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2263 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805d8ab400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 8 bytes inside of freed 512-byte region [ffff88805d8ab400, ffff88805d8ab600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5d8a8 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813ff26c80 ffffea0001742e00 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813ff26c80 ffffea0001742e00 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000002 ffffea0001762a01 00000000ffffffff 00000000ffffffff head: 0000000000000000 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 163, tgid 163 (kworker/u8:6), ts 94489384447, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3031 [inline] allocate_slab+0x96/0x3a0 mm/slub.c:3204 new_slab mm/slub.c:3258 [inline] ___slab_alloc+0xb12/0x13f0 mm/slub.c:4628 __slab_alloc+0xc6/0x1f0 mm/slub.c:4747 __slab_alloc_node mm/slub.c:4823 [inline] slab_alloc_node mm/slub.c:5234 [inline] __do_kmalloc_node mm/slub.c:5603 [inline] __kmalloc_noprof+0x14b/0x7d0 mm/slub.c:5616 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x142/0x860 net/ipv6/route.c:3809 addrconf_f6i_alloc+0x1d2/0x450 net/ipv6/route.c:4678 ipv6_add_addr+0x56e/0x10e0 net/ipv6/addrconf.c:1126 addrconf_add_linklocal+0x28f/0x600 net/ipv6/addrconf.c:3311 addrconf_addr_gen+0x490/0x580 net/ipv6/addrconf.c:3442 addrconf_init_auto_addrs+0x62d/0xa30 net/ipv6/addrconf.c:-1 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3740 page_owner free stack trace missing Memory state around the buggy address: ffff88805d8ab300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805d8ab380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805d8ab400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805d8ab480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805d8ab500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================