================================================================== BUG: KASAN: slab-out-of-bounds in __cache_seq_start net/sunrpc/cache.c:1351 [inline] BUG: KASAN: slab-out-of-bounds in cache_seq_start_rcu+0x3fe/0x420 net/sunrpc/cache.c:1399 Read of size 8 at addr ffff88801c301800 by task syz.2.603/8174 CPU: 1 UID: 0 PID: 8174 Comm: syz.2.603 Tainted: G U L syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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/0x1d0 mm/kasan/report.c:595 __cache_seq_start net/sunrpc/cache.c:1351 [inline] cache_seq_start_rcu+0x3fe/0x420 net/sunrpc/cache.c:1399 seq_read_iter+0x2c1/0x1270 fs/seq_file.c:226 seq_read+0x33b/0x4c0 fs/seq_file.c:163 pde_read fs/proc/inode.c:308 [inline] proc_reg_read+0x240/0x330 fs/proc/inode.c:320 vfs_read+0x1e4/0xb30 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:717 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5c3cd9cdd9 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:00007f5c3dc87028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f5c3d016360 RCX: 00007f5c3cd9cdd9 RDX: 000000000000067b RSI: 00002000000006c0 RDI: 000000000000002f RBP: 00007f5c3ce32d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5c3d0163f8 R14: 00007f5c3d016360 R15: 00007ffec7373438 Allocated by task 5627: 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] __do_kmalloc_node mm/slub.c:5295 [inline] __kmalloc_noprof+0x301/0x850 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] cache_create_net+0xa2/0x1f0 net/sunrpc/cache.c:1733 nfsd_idmap_init+0x62/0x250 fs/nfsd/nfs4idmap.c:470 nfsd_net_init+0x85/0x3e0 fs/nfsd/nfsctl.c:2212 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137 setup_net+0x118/0x3a0 net/core/net_namespace.c:446 copy_net_ns+0x46f/0x7c0 net/core/net_namespace.c:579 create_new_namespaces+0x3ea/0xac0 kernel/nsproxy.c:132 unshare_nsproxy_namespaces+0xf2/0x220 kernel/nsproxy.c:234 ksys_unshare+0x438/0xab0 kernel/fork.c:3243 __do_sys_unshare kernel/fork.c:3317 [inline] __se_sys_unshare kernel/fork.c:3315 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3315 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88801c301000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 0 bytes to the right of allocated 2048-byte region [ffff88801c301000, ffff88801c301800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88801c302000 pfn:0x1c300 head: order:3 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 ffff88813fe2f000 ffffea0001e3ba10 ffffea0000acc410 raw: ffff88801c302000 0000000800080005 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813fe2f000 ffffea0001e3ba10 ffffea0000acc410 head: ffff88801c302000 0000000800080005 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 3817463941, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab mm/slub.c:3467 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3525 refill_objects+0x277/0x420 mm/slub.c:7255 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5414 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] acpi_ds_create_walk_state+0x95/0x300 drivers/acpi/acpica/dswstate.c:518 acpi_ds_call_control_method+0x226/0xab0 drivers/acpi/acpica/dsmethod.c:511 acpi_ps_parse_aml+0xacd/0x1120 drivers/acpi/acpica/psparse.c:503 acpi_ps_execute_method+0x5c4/0xe90 drivers/acpi/acpica/psxface.c:190 acpi_ns_evaluate+0x640/0x1670 drivers/acpi/acpica/nseval.c:205 acpi_ut_evaluate_object+0xf7/0x610 drivers/acpi/acpica/uteval.c:60 acpi_ut_execute_STA+0xa6/0x300 drivers/acpi/acpica/uteval.c:223 acpi_ns_get_device_callback+0x23c/0x500 drivers/acpi/acpica/nsxfeval.c:723 acpi_ns_walk_namespace+0x4cc/0x760 drivers/acpi/acpica/nswalk.c:236 page_owner free stack trace missing Memory state around the buggy address: ffff88801c301700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801c301780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88801c301800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801c301880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801c301900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================