QAT: Invalid ioctl ================================================================== BUG: KASAN: use-after-free in handle_userfault+0x21c1/0x24c0 fs/userfaultfd.c:371 Read of size 8 at addr ffff8801d94ccd88 by task syz-executor4/10847 CPU: 1 PID: 10847 Comm: syz-executor4 Not tainted 4.15.0-rc1+ #198 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 handle_userfault+0x21c1/0x24c0 fs/userfaultfd.c:371 do_anonymous_page mm/memory.c:3121 [inline] handle_pte_fault mm/memory.c:3934 [inline] __handle_mm_fault+0x2e8c/0x3ad0 mm/memory.c:4060 handle_mm_fault+0x334/0x8d0 mm/memory.c:4097 __do_page_fault+0x5c9/0xc90 arch/x86/mm/fault.c:1429 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1504 page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1094 RIP: 0033:0x4529e5 RSP: 002b:0000000020013000 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 0000000000758020 RCX: 00000000004529d9 RDX: 0000000020059ffc RSI: 0000000020013000 RDI: 0000000000000400 RBP: 0000000000000047 R08: 0000000020058ffd R09: 0000000000000000 R10: 000000002005d000 R11: 0000000000000212 R12: 00000000006ed748 R13: 00000000ffffffff R14: 00007f18604206d4 R15: 0000000000000000 Allocated by task 10824: 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 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3547 dup_userfaultfd+0x21c/0x890 fs/userfaultfd.c:659 dup_mmap kernel/fork.c:662 [inline] dup_mm kernel/fork.c:1197 [inline] copy_mm+0xa38/0x1310 kernel/fork.c:1251 copy_process.part.36+0x1ec4/0x4ae0 kernel/fork.c:1753 copy_process kernel/fork.c:1566 [inline] _do_fork+0x1ef/0xff0 kernel/fork.c:2045 SYSC_clone kernel/fork.c:2155 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2149 do_syscall_64+0x26c/0x920 arch/x86/entry/common.c:285 return_from_SYSCALL_64+0x0/0x75 Freed by task 10824: 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:3491 [inline] kmem_cache_free+0x77/0x280 mm/slab.c:3749 userfaultfd_ctx_put+0x50c/0x740 fs/userfaultfd.c:165 userfaultfd_event_wait_completion+0x86d/0xae0 fs/userfaultfd.c:605 dup_fctx fs/userfaultfd.c:693 [inline] dup_userfaultfd_complete+0x2de/0x480 fs/userfaultfd.c:701 dup_mmap kernel/fork.c:730 [inline] dup_mm kernel/fork.c:1197 [inline] copy_mm+0xe9b/0x1310 kernel/fork.c:1251 copy_process.part.36+0x1ec4/0x4ae0 kernel/fork.c:1753 copy_process kernel/fork.c:1566 [inline] _do_fork+0x1ef/0xff0 kernel/fork.c:2045 SYSC_clone kernel/fork.c:2155 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2149 do_syscall_64+0x26c/0x920 arch/x86/entry/common.c:285 return_from_SYSCALL_64+0x0/0x75 The buggy address belongs to the object at ffff8801d94ccc00 which belongs to the cache userfaultfd_ctx_cache of size 400 The buggy address is located 392 bytes inside of 400-byte region [ffff8801d94ccc00, ffff8801d94ccd90) The buggy address belongs to the page: page:ffffea0007653300 count:1 mapcount:0 mapping:ffff8801d94cc000 index:0xffff8801d788bac0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801d94cc000 ffff8801d788bac0 0000000100000007 raw: ffffea000704b0a0 ffff8801d5440b40 ffff8801d5442900 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d94ccc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d94ccd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801d94ccd80: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801d94cce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d94cce80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================