================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:644 [inline] BUG: KASAN: slab-use-after-free in string+0x39c/0x3d0 lib/vsprintf.c:726 Read of size 1 at addr ffff8880220ab380 by task udevd/12366 CPU: 1 PID: 12366 Comm: udevd Not tainted 6.3.0-syzkaller-12378-gc8c655c34e33 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351 print_report mm/kasan/report.c:462 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:572 string_nocheck lib/vsprintf.c:644 [inline] string+0x39c/0x3d0 lib/vsprintf.c:726 vsnprintf+0xa36/0x1710 lib/vsprintf.c:2817 add_uevent_var+0x161/0x390 lib/kobject_uevent.c:665 dev_uevent+0x191/0x780 drivers/base/core.c:2575 uevent_show+0x1bc/0x380 drivers/base/core.c:2646 dev_attr_show+0x4f/0xd0 drivers/base/core.c:2349 sysfs_kf_seq_show+0x21d/0x430 fs/sysfs/file.c:59 seq_read_iter+0x4f9/0x12d0 fs/seq_file.c:230 kernfs_fop_read_iter+0x4ce/0x690 fs/kernfs/file.c:279 call_read_iter include/linux/fs.h:1862 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x6ab/0x950 fs/read_write.c:470 ksys_read+0x12b/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f8dc8716b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fff7ca5b888 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000557c7272cd60 RCX: 00007f8dc8716b6a RDX: 0000000000001000 RSI: 0000557c7275e060 RDI: 0000000000000008 RBP: 0000557c7272cd60 R08: 0000000000000008 R09: 0000000000008000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007fff7ca5bd68 R15: 000000000000000a Allocated by task 12361: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:559 [inline] raw_ioctl_init+0x152/0x830 drivers/usb/gadget/legacy/raw_gadget.c:460 raw_ioctl+0xbf5/0x2a60 drivers/usb/gadget/legacy/raw_gadget.c:1250 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 12361: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] __cache_free mm/slab.c:3389 [inline] __do_kmem_cache_free mm/slab.c:3576 [inline] __kmem_cache_free+0xcd/0x2c0 mm/slab.c:3583 dev_free+0x9a/0x700 drivers/usb/gadget/legacy/raw_gadget.c:210 kref_put include/linux/kref.h:65 [inline] raw_release+0x21d/0x2d0 drivers/usb/gadget/legacy/raw_gadget.c:424 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xad3/0x2960 kernel/exit.c:871 do_group_exit+0xd4/0x2a0 kernel/exit.c:1021 get_signal+0x2315/0x25b0 kernel/signal.c:2874 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880220ab380 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff8880220ab380, ffff8880220ab3a0) The buggy address belongs to the physical page: page:ffffea0000882ac0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880220abfc1 pfn:0x220ab flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0x2f() raw: 00fff00000000200 ffff888012440100 ffffea00013b7b10 ffffea0001ed1890 raw: ffff8880220abfc1 ffff8880220ab000 000000010000002f 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 5737, tgid 5721 (syz-executor.2), ts 156948833489, free_ts 112424901066 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1722 prep_new_page mm/page_alloc.c:1729 [inline] get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3493 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4759 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1360 [inline] cache_grow_begin+0x9b/0x3b0 mm/slab.c:2569 cache_alloc_refill+0x27f/0x380 mm/slab.c:2942 ____cache_alloc mm/slab.c:3018 [inline] ____cache_alloc mm/slab.c:3001 [inline] __do_cache_alloc mm/slab.c:3201 [inline] slab_alloc_node mm/slab.c:3249 [inline] __kmem_cache_alloc_node+0x360/0x3f0 mm/slab.c:3540 __do_kmalloc_node mm/slab_common.c:965 [inline] __kmalloc+0x4e/0x190 mm/slab_common.c:979 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:680 [inline] ops_init+0x16b/0x6b0 net/core/net_namespace.c:126 setup_net+0x5d1/0xc50 net/core/net_namespace.c:339 copy_net_ns+0x4ee/0x8e0 net/core/net_namespace.c:491 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228 ksys_unshare+0x449/0x920 kernel/fork.c:3444 __do_sys_unshare kernel/fork.c:3515 [inline] __se_sys_unshare kernel/fork.c:3513 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:3513 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2555 free_unref_page+0x33/0x370 mm/page_alloc.c:2650 slab_destroy mm/slab.c:1612 [inline] slabs_destroy+0x85/0xc0 mm/slab.c:1632 cache_flusharray mm/slab.c:3360 [inline] ___cache_free+0x2ae/0x3d0 mm/slab.c:3423 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x4f/0x1a0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x195/0x220 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:711 [inline] slab_alloc_node mm/slab.c:3256 [inline] __kmem_cache_alloc_node+0x1fc/0x3f0 mm/slab.c:3540 __do_kmalloc_node mm/slab_common.c:965 [inline] __kmalloc+0x4e/0x190 mm/slab_common.c:979 kmalloc include/linux/slab.h:563 [inline] inotify_handle_inode_event+0x120/0x5d0 fs/notify/inotify/inotify_fsnotify.c:89 inotify_ignored_and_remove_idr+0x28/0x70 fs/notify/inotify/inotify_user.c:527 fsnotify_free_mark+0xe9/0x140 fs/notify/mark.c:490 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:817 [inline] __se_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:794 [inline] __x64_sys_inotify_rm_watch+0x116/0x190 fs/notify/inotify/inotify_user.c:794 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8880220ab280: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8880220ab300: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc >ffff8880220ab380: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ^ ffff8880220ab400: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc ffff8880220ab480: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc ==================================================================