================================================================== BUG: KASAN: slab-out-of-bounds in should_fault_in_pages fs/gfs2/file.c:785 [inline] BUG: KASAN: slab-out-of-bounds in gfs2_file_buffered_write+0x576/0x900 fs/gfs2/file.c:1070 Read of size 8 at addr ffff88806267f700 by task syz.0.464/6595 CPU: 0 PID: 6595 Comm: syz.0.464 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 should_fault_in_pages fs/gfs2/file.c:785 [inline] gfs2_file_buffered_write+0x576/0x900 fs/gfs2/file.c:1070 gfs2_file_write_iter+0xfaf/0x1240 fs/gfs2/file.c:1145 do_iter_readv_writev+0x47e/0x5f0 fs/read_write.c:-1 do_iter_write+0x205/0x7b0 fs/read_write.c:855 iter_file_splice_write+0x699/0xcc0 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0xe1/0x130 fs/splice.c:956 splice_direct_to_actor+0x4ea/0xc10 fs/splice.c:902 do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008 do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f3bfbd73819 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:00007f3bf9fcd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f3bfbfecfa0 RCX: 00007f3bfbd73819 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 00007f3bfbe09c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000802000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3bfbfed038 R14: 00007f3bfbfecfa0 R15: 00007ffcfc4954a8 Allocated by task 6595: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc_array include/linux/slab.h:647 [inline] kcalloc include/linux/slab.h:676 [inline] iter_file_splice_write+0x19f/0xcc0 fs/splice.c:628 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0xe1/0x130 fs/splice.c:956 splice_direct_to_actor+0x4ea/0xc10 fs/splice.c:902 do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008 do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x189/0x950 kernel/rcu/tree.c:3091 fib_create_info+0x196e/0x24f0 net/ipv4/fib_semantics.c:1608 fib_table_insert+0xe4/0x1bb0 net/ipv4/fib_trie.c:1212 fib_magic+0x2e1/0x3c0 net/ipv4/fib_frontend.c:1106 fib_add_ifaddr+0x140/0x5e0 net/ipv4/fib_frontend.c:1128 fib_netdev_event+0x35c/0x480 net/ipv4/fib_frontend.c:1488 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] __dev_notify_flags+0x194/0x300 net/core/dev.c:8917 dev_change_flags+0xe3/0x1a0 net/core/dev.c:8955 do_setlink+0xcdb/0x3d60 net/core/rtnetlink.c:2781 __rtnl_newlink net/core/rtnetlink.c:3452 [inline] rtnl_newlink+0x1658/0x1a50 net/core/rtnetlink.c:3574 rtnetlink_rcv_msg+0x844/0xf30 net/core/rtnetlink.c:5684 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2072 __do_sys_sendto net/socket.c:2084 [inline] __se_sys_sendto net/socket.c:2080 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2080 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88806267f600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 0 bytes to the right of 256-byte region [ffff88806267f600, ffff88806267f700) The buggy address belongs to the page: page:ffffea0001899f80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6267e head:ffffea0001899f80 order:1 compound_mapcount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001988400 0000000700000007 ffff888016c41b40 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4197, ts 49182050249, free_ts 14935366544 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] __kmalloc+0x1cd/0x330 mm/slub.c:4408 kmalloc include/linux/slab.h:612 [inline] kzalloc include/linux/slab.h:738 [inline] new_dir fs/proc/proc_sysctl.c:959 [inline] get_subdir fs/proc/proc_sysctl.c:1004 [inline] __register_sysctl_table+0xa1f/0x1230 fs/proc/proc_sysctl.c:1353 mpls_dev_sysctl_register+0x1fe/0x2f0 net/mpls/af_mpls.c:1421 mpls_add_dev net/mpls/af_mpls.c:1476 [inline] mpls_dev_notify+0x2fa/0x780 net/mpls/af_mpls.c:1621 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] register_netdevice+0x12a6/0x1710 net/core/dev.c:10454 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:317 [inline] nsim_create+0x32d/0x3e0 drivers/net/netdevsim/netdev.c:365 __nsim_dev_port_add+0x698/0xab0 drivers/net/netdevsim/dev.c:1312 nsim_dev_port_add_all+0x37/0x100 drivers/net/netdevsim/dev.c:1372 nsim_dev_probe+0x763/0x9c0 drivers/net/netdevsim/dev.c:1513 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428 destroy_args+0xf0/0xa00 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336 do_one_initcall+0x272/0x730 init/main.c:1316 do_initcall_level+0x137/0x1f0 init/main.c:1389 do_initcalls+0x4b/0x90 init/main.c:1405 kernel_init_freeable+0x3e9/0x570 init/main.c:1629 kernel_init+0x19/0x1b0 init/main.c:1520 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff88806267f600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806267f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88806267f700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88806267f780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806267f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================