==================================================================
BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:681 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0x55c/0xae0 kernel/locking/mutex.c:747
Read of size 8 at addr ffff888058df9588 by task kworker/0:3/4314

CPU: 0 PID: 4314 Comm: kworker/0:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: kafsd afs_process_async_call
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline]
 __mutex_lock_common kernel/locking/mutex.c:681 [inline]
 __mutex_lock+0x55c/0xae0 kernel/locking/mutex.c:747
 rxrpc_kernel_recv_data+0x8f/0x510 net/rxrpc/recvmsg.c:712
 afs_extract_data+0x134/0x650 fs/afs/rxrpc.c:907
 afs_deliver_vl_get_capabilities+0x127/0x300 fs/afs/vlclient.c:329
 afs_deliver_to_call+0x140/0x1200 fs/afs/rxrpc.c:511
 afs_process_async_call+0x7e/0xe0 fs/afs/rxrpc.c:703
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 7877:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x18b/0x2f0 mm/slub.c:3383
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 rxrpc_alloc_call+0x263/0xbf0 net/rxrpc/call_object.c:128
 rxrpc_alloc_client_call net/rxrpc/call_object.c:204 [inline]
 rxrpc_new_client_call+0xe7/0xe10 net/rxrpc/call_object.c:293
 rxrpc_kernel_begin_call+0x48d/0x5e0 net/rxrpc/af_rxrpc.c:323
 afs_make_call+0x590/0x17d0 fs/afs/rxrpc.c:339
 afs_vl_get_capabilities+0x1c5/0x290 fs/afs/vlclient.c:408
 afs_do_probe_vlserver fs/afs/vl_probe.c:167 [inline]
 afs_send_vl_probes+0x363/0x620 fs/afs/vl_probe.c:200
 afs_select_vlserver+0xae0/0x1a00 fs/afs/vl_rotate.c:180
 afs_vl_get_cell_name fs/afs/vl_alias.c:286 [inline]
 yfs_check_canonical_cell_name fs/afs/vl_alias.c:308 [inline]
 afs_do_cell_detect_alias fs/afs/vl_alias.c:337 [inline]
 afs_cell_detect_alias+0x1f1/0x1170 fs/afs/vl_alias.c:374
 afs_validate_fc fs/afs/super.c:390 [inline]
 afs_get_tree+0x3ac/0x1170 fs/afs/super.c:565
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x247/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 5662:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0xf7/0x2a0 mm/slub.c:3709
 rxrpc_destroy_call+0x171/0x1f0 net/rxrpc/call_object.c:659
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
 insert_work+0x54/0x3c0 kernel/workqueue.c:1361
 __queue_work+0xae2/0xee0 kernel/workqueue.c:1520
 queue_work_on+0x124/0x1f0 kernel/workqueue.c:1548
 queue_work include/linux/workqueue.h:512 [inline]
 rxrpc_rcu_destroy_call+0x137/0x170 net/rxrpc/call_object.c:673
 rcu_do_batch kernel/rcu/tree.c:2297 [inline]
 rcu_core+0x9a3/0x1740 kernel/rcu/tree.c:2557
 handle_softirqs+0x291/0x910 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691

Second to last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
 call_rcu+0x14f/0x950 kernel/rcu/tree.c:2849
 afs_make_call+0x783/0x17d0 fs/afs/rxrpc.c:427
 afs_vl_get_capabilities+0x1c5/0x290 fs/afs/vlclient.c:408
 afs_do_probe_vlserver fs/afs/vl_probe.c:167 [inline]
 afs_send_vl_probes+0x363/0x620 fs/afs/vl_probe.c:200
 afs_select_vlserver+0xae0/0x1a00 fs/afs/vl_rotate.c:180
 afs_vl_get_cell_name fs/afs/vl_alias.c:286 [inline]
 yfs_check_canonical_cell_name fs/afs/vl_alias.c:308 [inline]
 afs_do_cell_detect_alias fs/afs/vl_alias.c:337 [inline]
 afs_cell_detect_alias+0x1f1/0x1170 fs/afs/vl_alias.c:374
 afs_validate_fc fs/afs/super.c:390 [inline]
 afs_get_tree+0x3ac/0x1170 fs/afs/super.c:565
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x247/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888058df9500
 which belongs to the cache rxrpc_call_jar of size 1168
The buggy address is located 136 bytes inside of
 1168-byte region [ffff888058df9500, ffff888058df9990)

The buggy address belongs to the physical page:
page:ffffea0001637e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888058df8fc0 pfn:0x58df8
head:ffffea0001637e00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88802ef1c500
raw: ffff888058df8fc0 00000000800c000a 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 4275, tgid 4275 (syz-executor), ts 76854173010, free_ts 22868746017
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560
 prep_new_page mm/page_alloc.c:2567 [inline]
 get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358
 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658
 alloc_slab_page+0x5d/0x180 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2d0 mm/slub.c:1997
 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x111/0x2f0 mm/slub.c:3383
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 rxrpc_alloc_call+0x263/0xbf0 net/rxrpc/call_object.c:128
 rxrpc_service_prealloc_one+0x45a/0xff0 net/rxrpc/call_accept.c:100
 rxrpc_kernel_charge_accept+0xd0/0x100 net/rxrpc/call_accept.c:490
 afs_charge_preallocation+0x3f8/0x580 fs/afs/rxrpc.c:739
 afs_open_socket+0x2a3/0x350 fs/afs/rxrpc.c:92
 afs_net_init+0x7b8/0x990 fs/afs/main.c:126
 ops_init+0x360/0x5e0 net/core/net_namespace.c:138
 setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336
 copy_net_ns+0x33e/0x5b0 net/core/net_namespace.c:508
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1487 [inline]
 free_pcp_prepare mm/page_alloc.c:1537 [inline]
 free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509
 free_contig_range+0x9d/0x150 mm/page_alloc.c:9626
 destroy_args+0xef/0xa0e mm/debug_vm_pgtable.c:1031
 debug_vm_pgtable+0x33c/0x38e mm/debug_vm_pgtable.c:1359
 do_one_initcall+0x257/0x800 init/main.c:1309
 do_initcall_level+0x13d/0x1ed init/main.c:1382
 do_initcalls+0x4b/0x8a init/main.c:1398
 kernel_init_freeable+0x401/0x5ab init/main.c:1637
 kernel_init+0x19/0x1b0 init/main.c:1525
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888058df9480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888058df9500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888058df9580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888058df9600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888058df9680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================