================================================================== BUG: KASAN: slab-out-of-bounds in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: slab-out-of-bounds in atomic_inc_not_zero include/asm-generic/atomic-instrumented.h:798 [inline] BUG: KASAN: slab-out-of-bounds in try_module_get+0x56/0x180 kernel/module.c:1142 Write of size 4 at addr ffff8881096749a8 by task syz.1.8874/32564 CPU: 1 PID: 32564 Comm: syz.1.8874 Tainted: G W 5.10.238-syzkaller-00282-gd76d4cd0623a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x280/0x290 mm/kasan/generic.c:189 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_inc_not_zero include/asm-generic/atomic-instrumented.h:798 [inline] try_module_get+0x56/0x180 kernel/module.c:1142 get_disk_and_module block/genhd.c:1790 [inline] exact_lock+0x6a/0xc0 block/genhd.c:677 kobj_lookup+0x298/0x430 drivers/base/map.c:119 get_gendisk+0xe9/0x340 block/genhd.c:1001 bdev_get_gendisk fs/block_dev.c:1110 [inline] __blkdev_get+0x1b0/0x12f0 fs/block_dev.c:1474 blkdev_get fs/block_dev.c:1653 [inline] blkdev_get_by_path+0x253/0x470 fs/block_dev.c:1690 mount_bdev+0x50/0x3a0 fs/super.c:1400 vfat_mount+0x34/0x40 fs/fat/namei_vfat.c:1057 legacy_get_tree+0xed/0x190 fs/fs_context.c:593 vfs_get_tree+0x89/0x260 fs/super.c:1572 do_new_mount+0x25a/0xa20 fs/namespace.c:2915 path_mount+0x572/0xc80 fs/namespace.c:3245 do_mount fs/namespace.c:3258 [inline] __do_sys_mount fs/namespace.c:3466 [inline] __se_sys_mount+0x318/0x380 fs/namespace.c:3443 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3443 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7eff0ac9f929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007eff09308038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007eff0aec6fa0 RCX: 00007eff0ac9f929 RDX: 0000200000001200 RSI: 00002000000000c0 RDI: 00002000000001c0 RBP: 00007eff0ad21b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007eff0aec6fa0 R15: 00007ffcec737fb8 Allocated by task 21535: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] __kmalloc+0x1a7/0x330 mm/slub.c:4033 kmalloc include/linux/slab.h:557 [inline] kzalloc include/linux/slab.h:664 [inline] __register_sysctl_table+0xeb/0x1250 fs/proc/proc_sysctl.c:1319 register_net_sysctl+0x2c/0x40 net/sysctl_net.c:121 __addrconf_sysctl_register+0x26e/0x3d0 net/ipv6/addrconf.c:7049 addrconf_sysctl_register+0x147/0x1a0 net/ipv6/addrconf.c:7096 ipv6_add_dev+0xbaf/0x10a0 net/ipv6/addrconf.c:448 addrconf_notify+0x582/0xe90 net/ipv6/addrconf.c:3567 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers+0x111/0x190 net/core/dev.c:2080 register_netdevice+0x1043/0x13c0 net/core/dev.c:10087 __ip_tunnel_create+0x2bf/0x380 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x290/0x740 net/ipv4/ip_tunnel.c:1083 ipgre_tap_init_net+0x29/0x30 net/ipv4/ip_gre.c:1701 ops_init+0x1ba/0x4a0 net/core/net_namespace.c:144 setup_net+0x36d/0xb50 net/core/net_namespace.c:345 copy_net_ns+0x314/0x520 net/core/net_namespace.c:486 create_new_namespaces+0x3a2/0x650 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x120/0x170 kernel/nsproxy.c:231 ksys_unshare+0x4ac/0x7d0 kernel/fork.c:3156 __do_sys_unshare kernel/fork.c:3224 [inline] __se_sys_unshare kernel/fork.c:3222 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3222 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff888109674000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 424 bytes to the right of 2048-byte region [ffff888109674000, ffff888109674800) The buggy address belongs to the page: page:ffffea0004259c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109670 head:ffffea0004259c00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 0000000000000000 0000000100000001 ffff888100042d80 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 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, ts 1794511434, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5357 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1808 [inline] new_slab+0x84/0x3f0 mm/slub.c:1869 new_slab_objects mm/slub.c:2627 [inline] ___slab_alloc+0x2a6/0x450 mm/slub.c:2791 __slab_alloc+0x63/0xa0 mm/slub.c:2831 slab_alloc_node mm/slub.c:2913 [inline] slab_alloc mm/slub.c:2955 [inline] kmem_cache_alloc_trace+0x1b3/0x2e0 mm/slub.c:2972 kmem_cache_alloc_node_trace include/linux/slab.h:440 [inline] kmalloc_node include/linux/slab.h:570 [inline] kzalloc_node include/linux/slab.h:675 [inline] __alloc_disk_node+0x79/0x580 block/genhd.c:1727 loop_add+0x33f/0x7b0 drivers/block/loop.c:2158 loop_init+0x1bf/0x1ff drivers/block/loop.c:2403 do_one_initcall+0x187/0x510 init/main.c:1197 do_initcall_level+0x16f/0x2cf init/main.c:1270 do_initcalls+0x50/0x92 init/main.c:1286 do_basic_setup+0x88/0x8f init/main.c:1306 kernel_init_freeable+0x287/0x3be init/main.c:1510 kernel_init+0x11/0x1a0 init/main.c:1397 page_owner free stack trace missing Memory state around the buggy address: ffff888109674880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888109674900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888109674980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888109674a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888109674a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================