VFS: Found a Xenix FS (block size = 1024) on device loop4 attempt to access beyond end of device loop4: rw=0, want=6491538, limit=128 Buffer I/O error on dev loop4, logical block 3245768, async page read ================================================================== BUG: KASAN: slab-out-of-bounds in sysv_new_inode+0xd74/0xeec fs/sysv/ialloc.c:153 Read of size 2 at addr ffff0000eac0c1ce by task syz.4.98/4468 CPU: 0 PID: 4468 Comm: syz.4.98 Not tainted 5.15.176-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x174/0x1e4 mm/kasan/report.c:451 __asan_report_load2_noabort+0x44/0x50 mm/kasan/report_generic.c:307 sysv_new_inode+0xd74/0xeec fs/sysv/ialloc.c:153 sysv_mknod+0x5c/0x100 fs/sysv/namei.c:53 sysv_create+0x38/0x4c fs/sysv/namei.c:67 vfs_create+0x2cc/0x434 fs/namei.c:3162 do_mknodat+0x314/0x694 fs/namei.c:3994 __do_sys_mknodat fs/namei.c:4022 [inline] __se_sys_mknodat fs/namei.c:4019 [inline] __arm64_sys_mknodat+0xb0/0xcc fs/namei.c:4019 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 4426: 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+0xbc/0xfc mm/kasan/common.c:513 __kasan_kmalloc+0x10/0x1c mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x27c/0x47c mm/slub.c:3247 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] mpls_add_dev net/mpls/af_mpls.c:1459 [inline] mpls_dev_notify+0x114/0x770 net/mpls/af_mpls.c:1621 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2018 [inline] call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers+0x138/0x1b8 net/core/dev.c:2044 register_netdevice+0xf28/0x12d4 net/core/dev.c:10396 tun_set_iff+0x620/0xaa0 drivers/net/tun.c:2802 __tun_chr_ioctl+0x85c/0x2dd4 drivers/net/tun.c:3062 tun_chr_ioctl+0x38/0x4c drivers/net/tun.c:3349 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 3641: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0x128/0x1ec mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0x178/0x410 mm/slub.c:4559 mpls_dev_destroy_rcu+0x4c/0x5c net/mpls/af_mpls.c:1495 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0x830/0x1b34 kernel/rcu/tree.c:2763 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2776 handle_softirqs+0x384/0xdbc kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] invoke_softirq kernel/softirq.c:439 [inline] __irq_exit_rcu+0x268/0x4d8 kernel/softirq.c:641 irq_exit+0x14/0x88 kernel/softirq.c:665 handle_domain_irq+0xf4/0x178 kernel/irq/irqdesc.c:711 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:765 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xd4/0x11c mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3007 [inline] call_rcu+0x118/0xb40 kernel/rcu/tree.c:3087 mpls_dev_notify+0x55c/0x770 net/mpls/af_mpls.c:1665 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2018 [inline] call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] unregister_netdevice_many+0xec4/0x189c net/core/dev.c:11102 unregister_netdevice_queue+0x2d0/0x31c net/core/dev.c:11035 unregister_netdevice include/linux/netdevice.h:3012 [inline] __tun_detach+0xb88/0x12dc drivers/net/tun.c:686 tun_detach drivers/net/tun.c:702 [inline] tun_chr_close+0x118/0x20c drivers/net/tun.c:3440 __fput+0x1c4/0x800 fs/file_table.c:280 ____fput+0x20/0x30 fs/file_table.c:308 task_work_run+0x130/0x1e4 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 The buggy address belongs to the object at ffff0000eac0c100 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 78 bytes to the right of 128-byte region [ffff0000eac0c100, ffff0000eac0c180) The buggy address belongs to the page: page:00000000d8a77874 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12ac0c flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 0000000000000000 0000000200000001 ffff0000c0002300 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000eac0c080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000eac0c100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000eac0c180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff0000eac0c200: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff0000eac0c280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== attempt to access beyond end of device loop4: rw=0, want=6491538, limit=128 Buffer I/O error on dev loop4, logical block 3245768, async page read