On Thu, Dec 28, 2017 at 12:15:01PM -0800, syzbot wrote: > Hello, > > syzkaller hit the following crash on > beacbc68ac3e23821a681adb30b45dc55b17488d > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > Unfortunately, I don't have any reproducer for this bug yet. > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+9cd6f6d80e1a5205f2f6@xxxxxxxxxxxxxxxxxxxxxxxxx > It will help syzbot understand when the bug is fixed. See footer for > details. > If you forward the report, please keep this part and the footer. > > ================================================================== > BUG: KASAN: use-after-free in mon_bin_vma_fault+0x378/0x400 > drivers/usb/mon/mon_bin.c:1238 > Read of size 8 at addr ffff8801cd040080 by task syz-executor1/5424 > > CPU: 1 PID: 5424 Comm: syz-executor1 Not tainted 4.15.0-rc5+ #238 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:17 [inline] > dump_stack+0x194/0x257 lib/dump_stack.c:53 > print_address_description+0x73/0x250 mm/kasan/report.c:252 > kasan_report_error mm/kasan/report.c:351 [inline] > kasan_report+0x25b/0x340 mm/kasan/report.c:409 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 > mon_bin_vma_fault+0x378/0x400 drivers/usb/mon/mon_bin.c:1238 > __do_fault+0xeb/0x30f mm/memory.c:3196 > do_read_fault mm/memory.c:3606 [inline] > do_fault mm/memory.c:3706 [inline] > handle_pte_fault mm/memory.c:3937 [inline] > __handle_mm_fault+0x1d8f/0x3ce0 mm/memory.c:4061 > handle_mm_fault+0x334/0x8d0 mm/memory.c:4098 > faultin_page mm/gup.c:502 [inline] > __get_user_pages+0x50c/0x15f0 mm/gup.c:699 > populate_vma_page_range+0x20e/0x2f0 mm/gup.c:1216 > __mm_populate+0x23a/0x450 mm/gup.c:1266 > mm_populate include/linux/mm.h:2226 [inline] > vm_mmap_pgoff+0x241/0x280 mm/util.c:338 > SYSC_mmap_pgoff mm/mmap.c:1533 [inline] > SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1491 > SYSC_mmap arch/x86/kernel/sys_x86_64.c:100 [inline] > SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:91 > entry_SYSCALL_64_fastpath+0x1f/0x96 > RIP: 0033:0x452ac9 > RSP: 002b:00007f7721b03c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000009 > RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ac9 > RDX: 0000000001000004 RSI: 0000000000004000 RDI: 0000000020ac6000 > RBP: 000000000000039b R08: 0000000000000014 R09: 0000000000000000 > R10: 0000000000008011 R11: 0000000000000212 R12: 00000000006f2728 > R13: 00000000ffffffff R14: 00007f7721b046d4 R15: 0000000000000000 > > Allocated by task 5424: > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 > set_track mm/kasan/kasan.c:459 [inline] > kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 > kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610 > kmalloc include/linux/slab.h:499 [inline] > kzalloc include/linux/slab.h:688 [inline] > mon_bin_open+0x1ae/0x4a0 drivers/usb/mon/mon_bin.c:703 > chrdev_open+0x257/0x730 fs/char_dev.c:417 > do_dentry_open+0x667/0xd40 fs/open.c:752 > vfs_open+0x107/0x220 fs/open.c:866 > do_last fs/namei.c:3379 [inline] > path_openat+0x1151/0x3530 fs/namei.c:3519 > do_filp_open+0x25b/0x3b0 fs/namei.c:3554 > do_sys_open+0x502/0x6d0 fs/open.c:1059 > SYSC_open fs/open.c:1077 [inline] > SyS_open+0x2d/0x40 fs/open.c:1072 > entry_SYSCALL_64_fastpath+0x1f/0x96 > > Freed by task 5433: > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 > set_track mm/kasan/kasan.c:459 [inline] > kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 > __cache_free mm/slab.c:3488 [inline] > kfree+0xd6/0x260 mm/slab.c:3803 > mon_bin_ioctl+0x68d/0xd40 drivers/usb/mon/mon_bin.c:1040 > vfs_ioctl fs/ioctl.c:46 [inline] > do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 > SYSC_ioctl fs/ioctl.c:701 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 > entry_SYSCALL_64_fastpath+0x1f/0x96 > > The buggy address belongs to the object at ffff8801cd040080 > which belongs to the cache kmalloc-2048 of size 2048 > The buggy address is located 0 bytes inside of > 2048-byte region [ffff8801cd040080, ffff8801cd040880) > The buggy address belongs to the page: > page:000000003d43a99d count:1 mapcount:0 mapping:0000000083654cb9 index:0x0 > compound_mapcount: 0 > flags: 0x2fffc0000008100(slab|head) > raw: 02fffc0000008100 ffff8801cd040080 0000000000000000 0000000100000003 > raw: ffffea00072a2e20 ffffea00071e6920 ffff8801db000c40 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801cd03ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff8801cd040000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > ffff8801cd040080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8801cd040100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801cd040180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please reply to this email with: > #syz fix: exact-commit-title No reproducer, but this seems to have stopped happening; I'm guessing it was fixed by commit 46eb14a6e158: #syz fix: USB: fix usbmon BUG trigger - Eric -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
