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KASAN: null-ptr-deref Read in kvm_arch_check_processor_compat

Status: closed as dup on 2020/06/30 06:11
Subsystems: kvm
[Documentation on labels]
Reported-by: syzbot+a99874f5323ce6088e53@syzkaller.appspotmail.com
First crash: 1400d, last: 1400d
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: WARNING in sysfs_warn_dup (log)
Repro: syz .config
  
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
general protection fault in syscall_return_slowpath kernel syz inconclusive done 1 1417d 1503d
Discussions (1)
Title Replies (including bot) Last reply
KASAN: null-ptr-deref Read in kvm_arch_check_processor_compat 1 (2) 2020/06/30 06:11

Sample crash report:
==================================================================
BUG: KASAN: null-ptr-deref in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
BUG: KASAN: null-ptr-deref in kvm_arch_check_processor_compat+0x1f8/0x750 arch/x86/kvm/x86.c:9818
Read of size 8 at addr 0000000000000060 by task syz-executor.2/8085

CPU: 1 PID: 8085 Comm: syz-executor.2 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 __kasan_report mm/kasan/report.c:517 [inline]
 kasan_report.cold+0x5/0x37 mm/kasan/report.c:530
 check_memory_region_inline mm/kasan/generic.c:186 [inline]
 check_memory_region+0x141/0x190 mm/kasan/generic.c:192
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
 kvm_arch_check_processor_compat+0x1f8/0x750 arch/x86/kvm/x86.c:9818
 </IRQ>
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 8085 Comm: syz-executor.2 Tainted: G    B             5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 end_report+0x4d/0x53 mm/kasan/report.c:104
 __kasan_report mm/kasan/report.c:520 [inline]
 kasan_report.cold+0xd/0x37 mm/kasan/report.c:530
 check_memory_region_inline mm/kasan/generic.c:186 [inline]
 check_memory_region+0x141/0x190 mm/kasan/generic.c:192
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
 kvm_arch_check_processor_compat+0x1f8/0x750 arch/x86/kvm/x86.c:9818
 </IRQ>
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/19 12:15 upstream 7ae77150d94d bc258b50 .config console log report syz ci-upstream-kasan-gce-selinux-root
* Struck through repros no longer work on HEAD.