================================================================== BUG: KASAN: use-after-free in dev_uevent+0x712/0x780 drivers/base/core.c:2320 Read of size 8 at addr ffff88802b934098 by task udevd/3689 CPU: 2 PID: 3689 Comm: udevd Not tainted 5.17.0-rc4-syzkaller-00229-g4f12b742eb2b #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 dev_uevent+0x712/0x780 drivers/base/core.c:2320 uevent_show+0x1b8/0x380 drivers/base/core.c:2391 dev_attr_show+0x4b/0x90 drivers/base/core.c:2094 sysfs_kf_seq_show+0x219/0x3d0 fs/sysfs/file.c:59 seq_read_iter+0x4f5/0x1280 fs/seq_file.c:230 kernfs_fop_read_iter+0x514/0x6f0 fs/kernfs/file.c:241 call_read_iter include/linux/fs.h:2068 [inline] new_sync_read+0x429/0x6e0 fs/read_write.c:400 vfs_read+0x35c/0x600 fs/read_write.c:481 ksys_read+0x12d/0x250 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f964cc558fe Code: c0 e9 e6 fe ff ff 50 48 8d 3d 0e c7 09 00 e8 c9 cf 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007ffc0133d258 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000056497b21a140 RCX: 00007f964cc558fe RDX: 0000000000001000 RSI: 000056497b218650 RDI: 0000000000000008 RBP: 00007f964cd22380 R08: 0000000000000008 R09: 00007f964cd25a60 R10: 0000000000000008 R11: 0000000000000246 R12: 000056497b21a140 R13: 0000000000000d68 R14: 00007f964cd21780 R15: 0000000000000d68 Allocated by task 4316: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:524 kasan_kmalloc include/linux/kasan.h:270 [inline] kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3567 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] dev_new drivers/usb/gadget/legacy/raw_gadget.c:183 [inline] raw_open+0x8d/0x4c0 drivers/usb/gadget/legacy/raw_gadget.c:373 misc_open+0x372/0x4a0 drivers/char/misc.c:141 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x1250 fs/open.c:824 do_open fs/namei.c:3476 [inline] path_openat+0x1c9e/0x2940 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 4315: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0xff/0x140 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] __cache_free mm/slab.c:3437 [inline] kfree+0xf8/0x2b0 mm/slab.c:3794 kref_put include/linux/kref.h:65 [inline] raw_release+0x218/0x290 drivers/usb/gadget/legacy/raw_gadget.c:412 __fput+0x286/0x9f0 fs/file_table.c:317 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88802b934000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 152 bytes inside of 4096-byte region [ffff88802b934000, ffff88802b935000) The buggy address belongs to the page: page:ffffea0000ae4d00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b934 head:ffffea0000ae4d00 order:1 compound_mapcount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00008be908 ffffea0000612d08 ffff888010c40900 raw: 0000000000000000 ffff88802b934000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 4316, ts 254636955499, free_ts 240714313612 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages_slowpath.constprop.0+0x2eb/0x20d0 mm/page_alloc.c:4934 __alloc_pages+0x412/0x500 mm/page_alloc.c:5402 __alloc_pages_node include/linux/gfp.h:572 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x390 mm/slab.c:2584 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957 ____cache_alloc mm/slab.c:3040 [inline] ____cache_alloc mm/slab.c:3023 [inline] __do_cache_alloc mm/slab.c:3267 [inline] slab_alloc mm/slab.c:3308 [inline] kmem_cache_alloc_trace+0x380/0x4a0 mm/slab.c:3565 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] dev_new drivers/usb/gadget/legacy/raw_gadget.c:183 [inline] raw_open+0x8d/0x4c0 drivers/usb/gadget/legacy/raw_gadget.c:373 misc_open+0x372/0x4a0 drivers/char/misc.c:141 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x1250 fs/open.c:824 do_open fs/namei.c:3476 [inline] path_openat+0x1c9e/0x2940 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4d0 fs/open.c:1214 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 slab_destroy mm/slab.c:1630 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1650 cache_flusharray mm/slab.c:3410 [inline] ___cache_free+0x303/0x600 mm/slab.c:3472 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x50/0x1a0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x97/0xb0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc_node mm/slab.c:3253 [inline] kmem_cache_alloc_node+0x2ea/0x590 mm/slab.c:3591 __alloc_skb+0x215/0x340 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1158 [inline] alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:5956 sock_alloc_send_pskb+0x793/0x920 net/core/sock.c:2586 unix_dgram_sendmsg+0x414/0x1a10 net/unix/af_unix.c:1896 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 __sys_sendto+0x21c/0x320 net/socket.c:2040 __do_sys_sendto net/socket.c:2052 [inline] __se_sys_sendto net/socket.c:2048 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2048 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88802b933f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802b934000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802b934080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802b934100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b934180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================