syzbot


UBSan: Undefined Behavior in db_nextframe (2)

Status: auto-obsoleted due to no activity on 2022/11/20 23:49
Reported-by: syzbot+d90ea4cd8be1624622e8@syzkaller.appspotmail.com
First crash: 621d, last: 621d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
netbsd UBSan: Undefined Behavior in db_nextframe (3) 1 145d 145d 0/3 auto-obsoleted due to no activity on 2024/03/10 18:16
netbsd UBSan: Undefined Behavior in db_nextframe 2 808d 815d 0/3 auto-closed as invalid on 2022/05/18 00:37

Sample crash report:
[ 209.6097795] panic: LOCKDEBUG: Kernel lock error: _kernel_lock,265: spinout
[ 209.6097795] cpu0: Begin traceback...
[ 209.6271147] vpanic() at netbsd:vpanic+0x2f2 sys/kern/subr_prf.c:293
[ 209.6771185] panic() at netbsd:panic+0x49 sys/kern/subr_prf.c:1033
[ 209.7071157] lockdebug_abort1() at netbsd:lockdebug_abort1+0x194 lockdebug_abort1 sys/kern/subr_lockdebug.c:790 [inline]
[ 209.7071157] lockdebug_abort1() at netbsd:lockdebug_abort1+0x194 sys/kern/subr_lockdebug.c:772
[ 209.7471171] _kernel_lock() at netbsd:_kernel_lock+0x4e5 sys/kern/kern_lock.c:265
[ 209.7771180] intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x23 x86_curcpu sys/arch/amd64/compile/obj/GENERIC_SYZKALLER/./machine/cpu.h:56 [inline]
[ 209.7771180] intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x23 sys/arch/x86/x86/intr.c:661
[ 209.7977178] Skipping crash dump on recursive panic
[ 209.7977178] panic: UBSan: Undefined Behavior in /syzkaller/managers/ci2-netbsd-kubsan/kernel/sys/arch/amd64/amd64/db_machdep.c:125:24, member access within misaligned address 0x1 for type 'struct x86_64_frame' which requires 8 byte alignment

[ 209.8242758] Faulted in mid-traceback; aborting...
[ 209.8288876] fatal breakpoint trap in supervisor mode
[ 209.8288876] trap type 1 code 0 rip 0xffffffff80221ab5 cs 0x8 rflags 0x246 cr2 0x776437f32000 ilevel 0x6 rsp 0xffffd28251454fb0
[ 209.8449947] curlwp 0xffffa962cd50ba80 pid 6034.6034 lowest kstack 0xffffd282514512c0
Stopped in pid 6034.6034 (syz-executor.4) at    netbsd:breakpoint+0x5:  leave
?
breakpoint() at netbsd:breakpoint+0x5
db_panic() at netbsd:db_panic+0xec sys/ddb/db_panic.c:69
vpanic() at netbsd:vpanic+0x2f2 sys/kern/subr_prf.c:293
Report() at netbsd:Report+0x3b sys/../common/lib/libc/misc/ubsan.c:1352
HandleTypeMismatch() at netbsd:HandleTypeMismatch+0xfc sys/../common/lib/libc/misc/ubsan.c:432
db_nextframe() at netbsd:db_nextframe+0x789 sys/arch/amd64/amd64/db_machdep.c:125
db_stack_trace_print() at netbsd:db_stack_trace_print+0x281 sys/arch/x86/x86/db_trace.c:277
db_panic() at netbsd:db_panic+0x9d x86_curcpu sys/arch/amd64/compile/obj/GENERIC_SYZKALLER/./machine/cpu.h:56 [inline]
db_panic() at netbsd:db_panic+0x9d sys/ddb/db_panic.c:59
vpanic() at netbsd:vpanic+0x2f2 sys/kern/subr_prf.c:293
panic() at netbsd:panic+0x49 sys/kern/subr_prf.c:1033
lockdebug_abort1() at netbsd:lockdebug_abort1+0x194 lockdebug_abort1 sys/kern/subr_lockdebug.c:790 [inline]
lockdebug_abort1() at netbsd:lockdebug_abort1+0x194 sys/kern/subr_lockdebug.c:772
_kernel_lock() at netbsd:_kernel_lock+0x4e5 sys/kern/kern_lock.c:265
intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x23 x86_curcpu sys/arch/amd64/compile/obj/GENERIC_SYZKALLER/./machine/cpu.h:56 [inline]
intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x23 sys/arch/x86/x86/intr.c:661
[ 209.8526098] Skipping crash dump on recursive panic
[ 209.8526098] panic: UBSan: Undefined Behavior in /syzkaller/managers/ci2-netbsd-kubsan/kernel/sys/arch/amd64/amd64/db_machdep.c:126:14, member access within misaligned address 0x1 for type 'struct x86_64_frame' which requires 8 byte alignment

[ 209.8526098] Faulted in mid-traceback; aborting...
[ 209.8526098] fatal breakpoint trap in supervisor mode
[ 209.8526098] trap type 1 code 0 rip 0xffffffff80221ab5 cs 0x8 rflags 0x246 cr2 0x776437f32000 ilevel 0x8 rsp 0xffffd28251453cb0
[ 209.8526098] curlwp 0xffffa962cd50ba80 pid 6034.6034 lowest kstack 0xffffd282514512c0
Stopped in pid 6034.6034 (syz-executor.4) at    netbsd:breakpoint+0x5:  leave

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/08/22 23:49 netbsd f12342b7f87d 26a13b38 .config console log report ci2-netbsd-kubsan UBSan: Undefined Behavior in db_nextframe
* Struck through repros no longer work on HEAD.