KASAN: null-ptr-deref Read in kvm_arch_check_processor

Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported
general protection fault in syscall_return_slowpath kernel	syz	inconclusive	done	1	1663d	1749d

syz

inconclusive

done

1663d

1749d

Title	Replies (including bot)	Last reply
KASAN: null-ptr-deref Read in kvm_arch_check_processor_compat	1 (2)	2020/06/30 06:11

================================================================== 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..