================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:645 [inline] BUG: KASAN: slab-use-after-free in string+0x394/0x3d0 lib/vsprintf.c:727 Read of size 1 at addr ffff888115928ac0 by task udevd/19467 CPU: 0 PID: 19467 Comm: udevd Not tainted 6.6.0-rc6-syzkaller-gec0989703642 #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+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 string_nocheck lib/vsprintf.c:645 [inline] string+0x394/0x3d0 lib/vsprintf.c:727 vsnprintf+0xc5f/0x1870 lib/vsprintf.c:2818 add_uevent_var+0x17c/0x390 lib/kobject_uevent.c:665 dev_uevent+0x18b/0x760 drivers/base/core.c:2575 uevent_show+0x1bf/0x380 drivers/base/core.c:2646 dev_attr_show+0x4f/0xd0 drivers/base/core.c:2349 sysfs_kf_seq_show+0x23e/0x400 fs/sysfs/file.c:59 seq_read_iter+0x4e5/0x1280 fs/seq_file.c:230 kernfs_fop_read_iter+0x4c8/0x680 fs/kernfs/file.c:279 call_read_iter include/linux/fs.h:1950 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4e0/0x930 fs/read_write.c:470 ksys_read+0x12f/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fcfc9e28b6a 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:00007ffd3dc281b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055bf3605ecf0 RCX: 00007fcfc9e28b6a RDX: 0000000000001000 RSI: 000055bf3605d070 RDI: 0000000000000008 RBP: 000055bf3605ecf0 R08: 0000000000000008 R09: 0000000000000020 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffd3dc28698 R15: 000000000000000a Allocated by task 19470: kasan_save_stack+0x33/0x50 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+0x87/0x90 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] raw_ioctl_init+0x163/0x840 drivers/usb/gadget/legacy/raw_gadget.c:473 raw_ioctl+0x9d9/0x2b80 drivers/usb/gadget/legacy/raw_gadget.c:1263 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 19470: kasan_save_stack+0x33/0x50 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:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x13c/0x190 mm/kasan/common.c:200 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+0xff/0x330 mm/slub.c:3822 dev_free+0x9a/0x700 drivers/usb/gadget/legacy/raw_gadget.c:211 kref_put include/linux/kref.h:65 [inline] raw_release+0x184/0x2e0 drivers/usb/gadget/legacy/raw_gadget.c:437 __fput+0x3f7/0xa70 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa92/0x2990 kernel/exit.c:874 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 get_signal+0x23c3/0x27a0 kernel/signal.c:2892 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x116/0x1f0 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888115928ac0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff888115928ac0, ffff888115928ae0) The buggy address belongs to the physical page: page:ffffea0004564a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115928 flags: 0x200000000000800(slab|node=0|zone=2) page_type: 0xffffffff() raw: 0200000000000800 ffff888100041500 ffffea000409da00 dead000000000002 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5903, tgid 5900 (syz-executor.2), ts 145796962003, free_ts 145628132462 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x10e1/0x2fd0 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2297 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x12c/0x310 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1022 [inline] __kmalloc_node_track_caller+0x50/0x100 mm/slab_common.c:1043 memdup_user+0x2a/0xd0 mm/util.c:197 raw_alloc_io_data drivers/usb/gadget/legacy/raw_gadget.c:637 [inline] raw_alloc_io_data+0x182/0x1c0 drivers/usb/gadget/legacy/raw_gadget.c:623 raw_ioctl_ep0_write drivers/usb/gadget/legacy/raw_gadget.c:725 [inline] raw_ioctl+0xa81/0x2b80 drivers/usb/gadget/legacy/raw_gadget.c:1272 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 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:1136 [inline] free_unref_page_prepare+0x460/0xa20 mm/page_alloc.c:2312 free_unref_page+0x33/0x2c0 mm/page_alloc.c:2405 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x4a/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc_lru+0x238/0x640 mm/slub.c:3509 alloc_inode_sb include/linux/fs.h:2868 [inline] shmem_alloc_inode+0x25/0x50 mm/shmem.c:4402 alloc_inode+0x5d/0x220 fs/inode.c:259 new_inode_pseudo fs/inode.c:1004 [inline] new_inode+0x22/0x260 fs/inode.c:1030 __shmem_get_inode+0x1a1/0xe40 mm/shmem.c:2449 shmem_get_inode mm/shmem.c:2546 [inline] shmem_mknod+0x66/0x1f0 mm/shmem.c:3214 lookup_open.isra.0+0x1049/0x1360 fs/namei.c:3495 open_last_lookups fs/namei.c:3563 [inline] path_openat+0x931/0x29c0 fs/namei.c:3793 do_filp_open+0x1de/0x430 fs/namei.c:3823 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1448 Memory state around the buggy address: ffff888115928980: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ffff888115928a00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc >ffff888115928a80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff888115928b00: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc ffff888115928b80: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ==================================================================