================================================================== 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 ffff88801c308800 by task syz.1.187/6929 CPU: 1 UID: 8 PID: 6929 Comm: syz.1.187 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [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 do_loop_readv_writev fs/read_write.c:849 [inline] do_loop_readv_writev fs/read_write.c:837 [inline] vfs_readv+0x5d8/0x8d0 fs/read_write.c:1022 do_readv+0x13e/0x340 fs/read_write.c:1082 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: 0033:0x7f15f079ce59 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:00007f15f1688028 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 00007f15f0a15fa0 RCX: 00007f15f079ce59 RDX: 0000000000000001 RSI: 0000200000000a80 RDI: 0000000000000003 RBP: 00007f15f0832d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f15f0a16038 R14: 00007f15f0a15fa0 R15: 00007ffd13eccfd8 Allocated by task 5635: 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 ffff88801c308000 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 [ffff88801c308000, ffff88801c308800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c308 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe34000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe34000 dead000000000100 dead000000000122 head: 0000000000000000 0000000800080008 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 3688846850, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 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:7271 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] pnp_alloc_dev+0x55/0x3f0 drivers/pnp/core.c:125 pnpacpi_add_device drivers/pnp/pnpacpi/core.c:234 [inline] pnpacpi_add_device_handler+0x1ee/0x800 drivers/pnp/pnpacpi/core.c:295 acpi_ns_get_device_callback+0x2bd/0x500 drivers/acpi/acpica/nsxfeval.c:740 acpi_ns_walk_namespace+0x4cc/0x760 drivers/acpi/acpica/nswalk.c:236 acpi_get_devices+0x119/0x1f0 drivers/acpi/acpica/nsxfeval.c:805 pnpacpi_init+0x99/0x100 drivers/pnp/pnpacpi/core.c:308 do_one_initcall+0x121/0x750 init/main.c:1392 do_initcall_level init/main.c:1454 [inline] do_initcalls init/main.c:1470 [inline] do_basic_setup init/main.c:1490 [inline] kernel_init_freeable+0x6ea/0x7b0 init/main.c:1703 kernel_init+0x1f/0x1e0 init/main.c:1593 page_owner free stack trace missing Memory state around the buggy address: ffff88801c308700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801c308780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88801c308800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88801c308880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801c308900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================