================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:644 [inline] BUG: KASAN: slab-use-after-free in string+0x394/0x3d0 lib/vsprintf.c:726 Read of size 1 at addr ffff888073168a80 by task udevd/4489 CPU: 1 PID: 4489 Comm: udevd Not tainted 6.5.0-rc3-next-20230728-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 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:644 [inline] string+0x394/0x3d0 lib/vsprintf.c:726 vsnprintf+0xc5f/0x1870 lib/vsprintf.c:2817 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:1942 [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: 0033:0x7f6f5db16b6a 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:00007ffd9ecfce38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055cd41661640 RCX: 00007f6f5db16b6a RDX: 0000000000001000 RSI: 000055cd417035a0 RDI: 000000000000000c RBP: 000055cd41661640 R08: 000000000000000c R09: 0000000000000001 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffd9ecfd318 R15: 000000000000000a Allocated by task 12542: 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+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] raw_ioctl_init+0x163/0x840 drivers/usb/gadget/legacy/raw_gadget.c:462 raw_ioctl+0x9d9/0x2b80 drivers/usb/gadget/legacy/raw_gadget.c:1252 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+0x18f/0x210 fs/ioctl.c:856 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 12542: 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+0x15e/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xb8/0x2f0 mm/slub.c:3822 dev_free+0x9a/0x700 drivers/usb/gadget/legacy/raw_gadget.c:210 kref_put include/linux/kref.h:65 [inline] raw_release+0x184/0x2e0 drivers/usb/gadget/legacy/raw_gadget.c:426 __fput+0x3fd/0xac0 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa99/0x2a20 kernel/exit.c:876 do_group_exit+0xd4/0x2a0 kernel/exit.c:1026 get_signal+0x23d1/0x27b0 kernel/signal.c:2892 arch_do_signal_or_restart+0x89/0x5f0 arch/x86/kernel/signal.c:308 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+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888073168a80 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of freed 32-byte region [ffff888073168a80, ffff888073168aa0) The buggy address belongs to the physical page: page:ffffea0001cc5a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x73168 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000200 ffff888012841500 ffffea0001dfb840 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5082, tgid 5082 (syz-executor.4), ts 325795599661, free_ts 325793809192 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2d2/0x350 mm/page_alloc.c:1569 prep_new_page mm/page_alloc.c:1576 [inline] get_page_from_freelist+0x10d7/0x31b0 mm/page_alloc.c:3256 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4512 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2279 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x24e/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8bc/0x1570 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+0x137/0x350 mm/slub.c:3517 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1115 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] ref_tracker_alloc+0x17c/0x5a0 lib/ref_tracker.c:203 __netns_tracker_alloc include/net/net_namespace.h:331 [inline] netns_tracker_alloc include/net/net_namespace.h:340 [inline] get_net_track include/net/net_namespace.h:357 [inline] sk_alloc+0x202/0x7f0 net/core/sock.c:2133 unix_create1+0xaa/0x930 net/unix/af_unix.c:983 unix_create+0x10e/0x1d0 net/unix/af_unix.c:1050 __sock_create+0x334/0x810 net/socket.c:1538 sock_create net/socket.c:1589 [inline] __sys_socket_create net/socket.c:1626 [inline] __sys_socket+0x13d/0x250 net/socket.c:1654 __do_sys_socket net/socket.c:1667 [inline] __se_sys_socket net/socket.c:1665 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1665 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1160 [inline] free_unref_page_prepare+0x508/0xb90 mm/page_alloc.c:2383 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2478 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18b/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] __kmem_cache_alloc_node+0x19b/0x350 mm/slub.c:3517 kmalloc_trace+0x25/0xe0 mm/slab_common.c:1115 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] mca_alloc net/ipv6/mcast.c:880 [inline] __ipv6_dev_mc_inc+0x2b7/0xc40 net/ipv6/mcast.c:936 addrconf_join_solict net/ipv6/addrconf.c:2181 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4003 [inline] addrconf_dad_work+0x232/0x13e0 net/ipv6/addrconf.c:4128 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2603 worker_thread+0x687/0x1110 kernel/workqueue.c:2754 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Memory state around the buggy address: ffff888073168980: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff888073168a00: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc >ffff888073168a80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ^ ffff888073168b00: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc ffff888073168b80: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc ==================================================================