rxrpc: Leaked peer 1cf {1} 127.0.0.1:7003 ================================================================== BUG: KASAN: slab-use-after-free in rxrpc_destroy_all_peers+0x1ce/0x1d0 net/rxrpc/peer_object.c:461 Read of size 8 at addr ffff888027a5a020 by task kworker/u8:6/181 CPU: 1 UID: 0 PID: 181 Comm: kworker/u8:6 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 rxrpc_destroy_all_peers+0x1ce/0x1d0 net/rxrpc/peer_object.c:461 rxrpc_exit_net+0x83/0xc0 net/rxrpc/net_ns.c:114 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252 cleanup_net+0x499/0x920 net/core/net_namespace.c:702 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 22636: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] rxrpc_alloc_peer+0xa7/0x400 net/rxrpc/peer_object.c:229 rxrpc_create_peer net/rxrpc/peer_object.c:293 [inline] rxrpc_lookup_peer+0x168/0x680 net/rxrpc/peer_object.c:354 rxrpc_kernel_lookup_peer+0xa8/0xe0 net/rxrpc/af_rxrpc.c:285 afs_merge_fs_addr4+0x1cd/0x4c0 fs/afs/addr_list.c:300 afs_parse_text_addrs+0x655/0xa10 fs/afs/addr_list.c:220 afs_alloc_cell fs/afs/cell.c:181 [inline] afs_lookup_cell+0xbb6/0x1940 fs/afs/cell.c:273 afs_proc_cells_write+0x2a3/0x3a0 fs/afs/proc.c:125 proc_simple_write+0x10e/0x1a0 fs/proc/generic.c:843 pde_write fs/proc/inode.c:330 [inline] proc_reg_write+0x240/0x330 fs/proc/inode.c:342 vfs_write+0x2aa/0x1050 fs/read_write.c:685 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 3: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] __rcu_free_sheaf_prepare+0x5d/0x2f0 mm/slub.c:2928 rcu_free_sheaf+0x1a/0xe0 mm/slub.c:5978 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2897 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 The buggy address belongs to the object at ffff888027a5a000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 32 bytes inside of freed 512-byte region [ffff888027a5a000, ffff888027a5a200) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888027a5ac00 pfn:0x27a58 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 ffff88813fe23c80 ffffea0000b10410 ffffea0000b40310 raw: ffff888027a5ac00 000000080010000f 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813fe23c80 ffffea0000b10410 ffffea0000b40310 head: ffff888027a5ac00 000000080010000f 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 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 0xd2000(__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 5014089488, free_ts 5013023549 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab mm/slub.c:3380 [inline] new_slab+0xa2/0x640 mm/slub.c:3426 refill_objects+0xe3/0x410 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __kmalloc_cache_noprof+0x479/0x6c0 mm/slub.c:5485 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] device_private_init drivers/base/core.c:3602 [inline] device_add+0xd3f/0x1970 drivers/base/core.c:3653 __add_disk+0x518/0xe40 block/genhd.c:492 add_disk_fwnode+0x118/0x480 block/genhd.c:593 add_disk include/linux/blkdev.h:800 [inline] nbd_dev_add+0x77a/0xb10 drivers/block/nbd.c:2021 nbd_init+0x291/0x2b0 drivers/block/nbd.c:2729 do_one_initcall+0x11d/0x700 init/main.c:1347 do_initcall_level init/main.c:1409 [inline] do_initcalls init/main.c:1425 [inline] do_basic_setup init/main.c:1445 [inline] kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658 kernel_init+0x1f/0x1e0 init/main.c:1548 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950 stack_depot_save_flags+0x435/0x9d0 lib/stackdepot.c:735 kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_node_noprof+0x27d/0x6b0 mm/slub.c:4989 blk_alloc_queue+0x31/0x790 block/blk-core.c:441 blk_mq_alloc_queue+0x174/0x290 block/blk-mq.c:4420 __blk_mq_alloc_disk+0x29/0x120 block/blk-mq.c:4467 nbd_dev_add+0x492/0xb10 drivers/block/nbd.c:1991 nbd_init+0x291/0x2b0 drivers/block/nbd.c:2729 do_one_initcall+0x11d/0x700 init/main.c:1347 do_initcall_level init/main.c:1409 [inline] do_initcalls init/main.c:1425 [inline] do_basic_setup init/main.c:1445 [inline] kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658 kernel_init+0x1f/0x1e0 init/main.c:1548 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888027a59f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888027a59f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888027a5a000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888027a5a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027a5a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================