================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:645 [inline] BUG: KASAN: slab-use-after-free in string+0x218/0x2b0 lib/vsprintf.c:727 Read of size 1 at addr ffff888062746c04 by task udevd/6186 CPU: 1 PID: 6186 Comm: udevd Not tainted 6.6.0-rc5-syzkaller-g94f6f0550c62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 string_nocheck lib/vsprintf.c:645 [inline] string+0x218/0x2b0 lib/vsprintf.c:727 vsnprintf+0x10fc/0x1d80 lib/vsprintf.c:2818 add_uevent_var+0x1c4/0x440 lib/kobject_uevent.c:665 dev_uevent+0x3ec/0x8f0 drivers/base/core.c:2575 uevent_show+0x19a/0x310 drivers/base/core.c:2646 dev_attr_show+0x54/0xc0 drivers/base/core.c:2349 sysfs_kf_seq_show+0x331/0x4b0 fs/sysfs/file.c:59 seq_read_iter+0x43e/0xd10 fs/seq_file.c:230 call_read_iter include/linux/fs.h:1950 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x795/0xb00 fs/read_write.c:470 ksys_read+0x1a0/0x2c0 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa896116b6a 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:00007ffd78981b18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000562c15925200 RCX: 00007fa896116b6a RDX: 0000000000001000 RSI: 0000562c159238a0 RDI: 0000000000000008 RBP: 0000562c15925200 R08: 0000000000000008 R09: 0000000000000040 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffd78981ff8 R15: 000000000000000a Allocated by task 14157: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] raw_ioctl_init drivers/usb/gadget/legacy/raw_gadget.c:462 [inline] raw_ioctl+0x1aad/0x3cd0 drivers/usb/gadget/legacy/raw_gadget.c:1252 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 14157: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3822 dev_free drivers/usb/gadget/legacy/raw_gadget.c:210 [inline] kref_put+0xb5/0x7c0 include/linux/kref.h:65 raw_release+0x138/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:426 __fput+0x3f8/0x910 fs/file_table.c:384 task_work_run+0x24a/0x300 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa2c/0x2650 kernel/exit.c:874 do_group_exit+0x206/0x2c0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888062746c00 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 4 bytes inside of freed 32-byte region [ffff888062746c00, ffff888062746c20) The buggy address belongs to the physical page: page:ffffea000189d180 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x62746 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888012841500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000400040 00000001ffffffff 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 0x112c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 4484, tgid 4484 (udevd), ts 126714760489, free_ts 126681770211 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x31db/0x3360 mm/page_alloc.c:3170 __alloc_pages+0x255/0x670 mm/page_alloc.c:4426 alloc_slab_page+0x6a/0x160 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xc85/0x1310 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc+0xa8/0x230 mm/slab_common.c:1036 kmalloc include/linux/slab.h:603 [inline] kzalloc include/linux/slab.h:720 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26f/0x530 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x598/0x5e0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x23a/0x870 security/tomoyo/file.c:723 tomoyo_path_mknod+0x176/0x1b0 security/tomoyo/tomoyo.c:251 security_path_mknod+0xf5/0x150 security/security.c:1715 may_o_create fs/namei.c:3317 [inline] lookup_open fs/namei.c:3458 [inline] open_last_lookups fs/namei.c:3563 [inline] path_openat+0xc38/0x3180 fs/namei.c:3793 do_filp_open+0x234/0x490 fs/namei.c:3823 do_sys_openat2+0x13e/0x1d0 fs/open.c:1422 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x8c3/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 __slab_free+0x2f6/0x390 mm/slub.c:3715 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x67/0x3d0 mm/slab.h:762 slab_alloc_node mm/slub.c:3478 [inline] __kmem_cache_alloc_node+0x141/0x270 mm/slub.c:3517 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1114 kmalloc include/linux/slab.h:599 [inline] raw_ioctl_init drivers/usb/gadget/legacy/raw_gadget.c:462 [inline] raw_ioctl+0x1aad/0x3cd0 drivers/usb/gadget/legacy/raw_gadget.c:1252 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888062746b00: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff888062746b80: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc >ffff888062746c00: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ^ ffff888062746c80: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff888062746d00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ==================================================================