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BUG: KASAN: vmalloc-out-of-bounds in __list_add_valid+0x67/0xe0 lib/list_debug.c:30
Read of size 8 at addr ffffc9000372f930 by task syz.3.294/5132

CPU: 0 PID: 5132 Comm: syz.3.294 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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
 __list_add_valid+0x67/0xe0 lib/list_debug.c:30
 __list_add include/linux/list.h:72 [inline]
 list_add_tail include/linux/list.h:109 [inline]
 rpc_queue_upcall+0x82/0x320 net/sunrpc/rpc_pipe.c:142
 __cld_pipe_upcall fs/nfsd/nfs4recover.c:739 [inline]
 cld_pipe_upcall fs/nfsd/nfs4recover.c:762 [inline]
 nfsd4_cld_grace_start fs/nfsd/nfs4recover.c:1397 [inline]
 nfsd4_cld_tracking_init+0xce1/0x1230 fs/nfsd/nfs4recover.c:1593
 nfsd4_client_tracking_init+0x190/0x3c0 fs/nfsd/nfs4recover.c:2013
 nfs4_state_start_net+0xb0e/0x10a0 fs/nfsd/nfs4state.c:8358
 nfsd_startup_net fs/nfsd/nfssvc.c:433 [inline]
 nfsd_svc+0x63d/0xab0 fs/nfsd/nfssvc.c:801
 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:424
 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
 vfs_write+0x2dc/0x9a0 fs/read_write.c:582
 ksys_write+0x14d/0x260 fs/read_write.c:637
 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
RIP: 0033:0x7faddc99e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007faddd8bd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007faddcc25fa0 RCX: 00007faddc99e159
RDX: 0000000000000002 RSI: 0000200000000540 RDI: 0000000000000004
RBP: 00007faddca3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faddcc26038 R14: 00007faddcc25fa0 R15: 00007ffe2d71da98
 </TASK>

The buggy address belongs to stack of task syz.3.294/5132
 and is located at offset 112 in frame:
 nfsd4_cld_tracking_init+0x0/0x1230

This frame has 2 objects:
 [32, 80) 'msg.i.i.i61'
 [112, 160) 'msg.i.i.i'

The buggy address belongs to a 8-page vmalloc region starting at 0xffffc90003728000 allocated at copy_process+0x621/0x4070 kernel/fork.c:2192
The buggy address belongs to the physical page:
page:ffffea0000bc6b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f1ac
memcg:ffff88802fbdbd82
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88802fbdbd82
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 5120, tgid 5120 (syz.1.289), ts 118682747729, free_ts 103791325226
 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
 vm_area_alloc_pages mm/vmalloc.c:3059 [inline]
 __vmalloc_area_node mm/vmalloc.c:3128 [inline]
 __vmalloc_node_range+0x94a/0x1380 mm/vmalloc.c:3300
 alloc_thread_stack_node kernel/fork.c:313 [inline]
 dup_task_struct+0x3c8/0x700 kernel/fork.c:995
 copy_process+0x621/0x4070 kernel/fork.c:2192
 kernel_clone+0x24b/0x900 kernel/fork.c:2765
 __do_sys_clone3 kernel/fork.c:3064 [inline]
 __se_sys_clone3+0x32d/0x3f0 kernel/fork.c:3048
 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
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
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
 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]
 __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa3/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 tomoyo_realpath_from_path+0xe2/0x5c0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x26f/0x610 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x120 security/security.c:1365
 vfs_getattr+0x26/0x3a0 fs/stat.c:158
 vfs_fstat fs/stat.c:183 [inline]
 __do_sys_newfstat fs/stat.c:447 [inline]
 __se_sys_newfstat fs/stat.c:444 [inline]
 __x64_sys_newfstat+0x13d/0x220 fs/stat.c:444
 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

Memory state around the buggy address:
 ffffc9000372f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000372f880: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
>ffffc9000372f900: 00 00 f2 f2 f2 f2 f8 f8 f8 f8 f8 f8 f3 f3 f3 f3
                                     ^
 ffffc9000372f980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000372fa00: f1 f1 f1 f1 00 00 f3 f3 00 00 00 00 00 00 00 00
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