sorry forget to sent to LKML earlier Rondreis <linhaoguo86@xxxxxxxxx> 于2022年8月31日周三 16:10写道： > > Hello, > > When fuzzing the Linux kernel driver v5.18.0, the following crash was triggered. > > HEAD commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f > git tree: upstream > > kernel config: https://pastebin.com/h9YFR4Vq > C reproducer: https://pastebin.com/fdusnCsb > console output: https://pastebin.com/HcL6UmE1 > > Basically, in the c reproducer, we use the gadget module to emulate > the process of attaching a usb device (vendor id: 0xbb4, product id: > 0xa79, with function: @phonet). > To reproduce this crash, we utilize a third-party library to emulate > the attaching process: https://github.com/linux-usb-gadgets/libusbgx. > Just clone this repository, make install it, and compile the c > reproducer with ``` gcc crash.c -lusbgx -lconfig -o crash ``` will do > the trick. > > It would be so appreciate if you have any ideal how to solve this bug. > > The crash report is as follow: > > ``` > ================================================================== > BUG: KASAN: use-after-free in free_netdev+0x4d9/0x5a0 net/core/dev.c:10599 > Read of size 1 at addr ffff88802a5485c8 by task syz-executor.0/11237 > > CPU: 2 PID: 11237 Comm: syz-executor.0 Not tainted 5.18.0 #2 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > 1.13.0-1ubuntu1.1 04/01/2014 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 > print_address_description mm/kasan/report.c:313 [inline] > print_report.cold+0xe5/0x659 mm/kasan/report.c:429 > kasan_report+0x8a/0x1b0 mm/kasan/report.c:491 > free_netdev+0x4d9/0x5a0 net/core/dev.c:10599 > phonet_free_inst+0x92/0xb0 drivers/usb/gadget/function/f_phonet.c:618 > usb_put_function_instance+0x7f/0xb0 drivers/usb/gadget/functions.c:77 > config_item_cleanup fs/configfs/item.c:128 [inline] > config_item_release+0x11d/0x2f0 fs/configfs/item.c:137 > kref_put include/linux/kref.h:65 [inline] > config_item_put+0x7c/0xa0 fs/configfs/item.c:149 > configfs_rmdir+0x69f/0xa70 fs/configfs/dir.c:1538 > vfs_rmdir fs/namei.c:4017 [inline] > vfs_rmdir+0x2a0/0x640 fs/namei.c:3994 > do_rmdir+0x328/0x390 fs/namei.c:4078 > __do_sys_rmdir fs/namei.c:4097 [inline] > __se_sys_rmdir fs/namei.c:4095 [inline] > __x64_sys_rmdir+0x3e/0x50 fs/namei.c:4095 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x7f84aa0a69cb > Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 > 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 54 00 00 00 0f 05 <48> 3d > 01 f0 ff ff8 > RSP: 002b:00007f84aa7cda88 EFLAGS: 00000293 ORIG_RAX: 0000000000000054 > RAX: ffffffffffffffda RBX: 00007f84a4001c10 RCX: 00007f84aa0a69cb > RDX: 00007f84a40021c0 RSI: 00007f84aa114825 RDI: 00007f84aa7cda90 > RBP: 00007f84aa7cda90 R08: 00007f84aa114825 R09: 00007f84aa7cd910 > R10: 00000000fffffff4 R11: 0000000000000293 R12: 0000000000000000 > R13: 0000000000000001 R14: 00007f84a4001b70 R15: 00007f84aa198020 > </TASK> > > Allocated by task 11185: > 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+0xa9/0xd0 mm/kasan/common.c:524 > kasan_kmalloc include/linux/kasan.h:234 [inline] > __kmalloc_node+0x1fc/0x450 mm/slub.c:4462 > kmalloc_node include/linux/slab.h:604 [inline] > kvmalloc_node+0x3e/0x190 mm/util.c:580 > kvmalloc include/linux/slab.h:731 [inline] > kvzalloc include/linux/slab.h:739 [inline] > alloc_netdev_mqs+0x9d/0x11b0 net/core/dev.c:10491 > gphonet_setup_default+0x34/0x80 drivers/usb/gadget/function/f_phonet.c:697 > phonet_alloc_inst+0x80/0x130 drivers/usb/gadget/function/f_phonet.c:631 > try_get_usb_function_instance+0x122/0x1e0 drivers/usb/gadget/functions.c:28 > usb_get_function_instance+0x13/0xa0 drivers/usb/gadget/functions.c:44 > function_make+0x105/0x3e0 drivers/usb/gadget/configfs.c:605 > configfs_mkdir+0x46a/0xb90 fs/configfs/dir.c:1327 > vfs_mkdir+0x620/0x980 fs/namei.c:3931 > do_mkdirat+0x242/0x2b0 fs/namei.c:3957 > __do_sys_mkdir fs/namei.c:3977 [inline] > __se_sys_mkdir fs/namei.c:3975 [inline] > __x64_sys_mkdir+0x61/0x80 fs/namei.c:3975 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > > Freed by task 11185: > 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 mm/kasan/common.c:328 [inline] > __kasan_slab_free+0x11d/0x190 mm/kasan/common.c:374 > kasan_slab_free include/linux/kasan.h:200 [inline] > slab_free_hook mm/slub.c:1728 [inline] > slab_free_freelist_hook mm/slub.c:1754 [inline] > slab_free mm/slub.c:3510 [inline] > kfree+0xec/0x4b0 mm/slub.c:4552 > kvfree+0x42/0x50 mm/util.c:622 > netdev_freemem net/core/dev.c:10445 [inline] > free_netdev+0x46b/0x5a0 net/core/dev.c:10628 > gphonet_register_netdev drivers/usb/gadget/function/f_phonet.c:720 [inline] > pn_bind+0x4cb/0x590 drivers/usb/gadget/function/f_phonet.c:502 > usb_add_function+0x217/0x930 drivers/usb/gadget/composite.c:337 > configfs_composite_bind+0x8b6/0x11b0 drivers/usb/gadget/configfs.c:1392 > udc_bind_to_driver+0x1f4/0x7b0 drivers/usb/gadget/udc/core.c:1504 > usb_gadget_probe_driver+0x335/0x410 drivers/usb/gadget/udc/core.c:1571 > gadget_dev_desc_UDC_store+0x17b/0x220 drivers/usb/gadget/configfs.c:287 > flush_write_buffer fs/configfs/file.c:207 [inline] > configfs_write_iter+0x2ea/0x480 fs/configfs/file.c:229 > call_write_iter include/linux/fs.h:2050 [inline] > new_sync_write+0x393/0x570 fs/read_write.c:504 > vfs_write+0x7c4/0xab0 fs/read_write.c:591 > ksys_write+0x127/0x250 fs/read_write.c:644 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > > The buggy address belongs to the object at ffff88802a548000 > which belongs to the cache kmalloc-cg-4k of size 4096 > The buggy address is located 1480 bytes inside of > 4096-byte region [ffff88802a548000, ffff88802a549000) > > The buggy address belongs to the physical page: > page:ffffea0000a95200 refcount:1 mapcount:0 mapping:0000000000000000 > index:0x0 pfn:0x2a548 > head:ffffea0000a95200 order:3 compound_mapcount:0 compound_pincount:0 > memcg:ffff88801aa7a841 > flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) > raw: 00fff00000010200 0000000000000000 dead000000000001 ffff88801184c140 > raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88801aa7a841 > page dumped because: kasan: bad access detected > page_owner tracks the page as allocated > page last allocated via order 3, migratetype Unmovable, gfp_mask > 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), > pid7 > set_page_owner include/linux/page_owner.h:31 [inline] > post_alloc_hook mm/page_alloc.c:2434 [inline] > prep_new_page+0x297/0x330 mm/page_alloc.c:2441 > get_page_from_freelist+0x210e/0x3ab0 mm/page_alloc.c:4182 > __alloc_pages+0x30c/0x6e0 mm/page_alloc.c:5408 > alloc_pages+0x119/0x250 mm/mempolicy.c:2272 > alloc_slab_page mm/slub.c:1799 [inline] > allocate_slab mm/slub.c:1944 [inline] > new_slab+0x2a9/0x3f0 mm/slub.c:2004 > ___slab_alloc+0xc62/0x1080 mm/slub.c:3005 > __slab_alloc.isra.0+0x4d/0xa0 mm/slub.c:3092 > slab_alloc_node mm/slub.c:3183 [inline] > __kmalloc_node+0x340/0x450 mm/slub.c:4458 > kmalloc_node include/linux/slab.h:604 [inline] > kvmalloc_node+0x3e/0x190 mm/util.c:580 > kvmalloc include/linux/slab.h:731 [inline] > seq_buf_alloc fs/seq_file.c:38 [inline] > seq_read_iter+0x800/0x11e0 fs/seq_file.c:210 > kernfs_fop_read_iter+0x446/0x5f0 fs/kernfs/file.c:236 > call_read_iter include/linux/fs.h:2044 [inline] > new_sync_read+0x38d/0x600 fs/read_write.c:401 > vfs_read+0x495/0x5d0 fs/read_write.c:482 > ksys_read+0x127/0x250 fs/read_write.c:620 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0x80 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:1356 [inline] > free_pcp_prepare+0x51f/0xd00 mm/page_alloc.c:1406 > free_unref_page_prepare mm/page_alloc.c:3328 [inline] > free_unref_page+0x19/0x5b0 mm/page_alloc.c:3423 > __unfreeze_partials+0x3d2/0x3f0 mm/slub.c:2523 > do_slab_free mm/slub.c:3498 [inline] > ___cache_free+0x12c/0x140 mm/slub.c:3517 > qlink_free mm/kasan/quarantine.c:157 [inline] > qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:176 > kasan_quarantine_reduce+0x13d/0x180 mm/kasan/quarantine.c:283 > __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 > kasan_slab_alloc include/linux/kasan.h:224 [inline] > slab_post_alloc_hook+0x4d/0x4f0 mm/slab.h:749 > slab_alloc_node mm/slub.c:3217 [inline] > slab_alloc mm/slub.c:3225 [inline] > __kmem_cache_alloc_lru mm/slub.c:3232 [inline] > kmem_cache_alloc+0x1be/0x460 mm/slub.c:3242 > kmem_cache_zalloc include/linux/slab.h:704 [inline] > __kernfs_new_node+0xd4/0x8b0 fs/kernfs/dir.c:585 > kernfs_new_node+0x93/0x120 fs/kernfs/dir.c:647 > kernfs_create_dir_ns+0x48/0x150 fs/kernfs/dir.c:1003 > internal_create_group+0x7ab/0xba0 fs/sysfs/group.c:136 > netdev_queue_add_kobject net/core/net-sysfs.c:1659 [inline] > netdev_queue_update_kobjects+0x398/0x4d0 net/core/net-sysfs.c:1705 > register_queue_kobjects net/core/net-sysfs.c:1766 [inline] > netdev_register_kobject+0x35d/0x430 net/core/net-sysfs.c:2012 > register_netdevice+0xb60/0x1290 net/core/dev.c:9961 > > Memory state around the buggy address: > ffff88802a548480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff88802a548500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > >ffff88802a548580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff88802a548600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff88802a548680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > ```
