diff options
Diffstat (limited to 'results/classifier/user-mode-bugs/1267')
| -rw-r--r-- | results/classifier/user-mode-bugs/1267 | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/results/classifier/user-mode-bugs/1267 b/results/classifier/user-mode-bugs/1267 new file mode 100644 index 000000000..a79cab438 --- /dev/null +++ b/results/classifier/user-mode-bugs/1267 @@ -0,0 +1,95 @@ + + +qemu-i386 missing VDSO +Description of problem: +Qemu crashes with a segmentation fault when running any binary using qemu-i386. Steps to reproduce are trivial, simply run `qemu-user ./test`. The file is here: [test](/uploads/fe0d498713e79d7e39f417e69ad64c2f/test). Basically any binary compiled with `GOARCH=386` using [TinyGo](https://tinygo.org/) should reproduce this issue. +I also tried some trivial Go compiled binary and they also crash, but this time with an internal Go error that suggests something is terribly broken over there too: `fatal error: mallocgc called without a P or outside bootstrapping` + +Interestingly, qemu-x86_64 and qemu-arm appear to work just fine. + +Unfortunately I couldn't get a good backtrace on newer versions. It looks like this in the git version, which I doubt is correct: + +``` +~/src/qemu/build$ /bin/lldb ./qemu-i386 +(lldb) target create "./qemu-i386" +Current executable set to '/home/ayke/src/qemu/build/qemu-i386' (aarch64). +(lldb) run /home/ayke/src/tinygo/tinygo/test +Process 97986 launched: '/home/ayke/src/qemu/build/qemu-i386' (aarch64) +Process 97986 stopped +* thread #1, name = 'qemu-i386', stop reason = unknown crash reason + frame #0: 0x0000fffff78fb9fc libc.so.6`__sigsuspend + 92 +libc.so.6`__sigsuspend: +-> 0xfffff78fb9fc <+92>: svc #0 + 0xfffff78fba00 <+96>: cmn x0, #0x1, lsl #12 ; =0x1000 + 0xfffff78fba04 <+100>: b.hi 0xfffff78fba3c ; <+156> + 0xfffff78fba08 <+104>: mov w19, w0 +(lldb) bt +* thread #1, name = 'qemu-i386', stop reason = unknown crash reason + * frame #0: 0x0000fffff78fb9fc libc.so.6`__sigsuspend + 92 + frame #1: 0x0000aaaaaabfcedc qemu-i386`dump_core_and_abort(target_sig=11) at signal.c:745:5 + frame #2: 0x0000aaaaaabfc128 qemu-i386`handle_pending_signal(cpu_env=0x0000aaaaaae5d2e0, sig=11, k=0x0000aaaaaae68af8) at signal.c:1061:13 + frame #3: 0x0000aaaaaabfbe48 qemu-i386`process_pending_signals(cpu_env=0x0000aaaaaae5d2e0) at signal.c:1141:13 + frame #4: 0x0000aaaaaaae5a04 qemu-i386`cpu_loop(env=0x0000aaaaaae5d2e0) at cpu_loop.c:315:9 + frame #5: 0x0000aaaaaabf5e7c qemu-i386`main(argc=2, argv=0x0000ffffffffecd8, envp=0x0000ffffffffecf0) at main.c:925:5 + frame #6: 0x0000fffff78e7b80 libc.so.6`___lldb_unnamed_symbol2945 + 112 + frame #7: 0x0000fffff78e7c60 libc.so.6`__libc_start_main + 160 + frame #8: 0x0000aaaaaaae0430 qemu-i386`_start at start.S:81 +(lldb) ^D +``` + +I got a better (but still not great) backtrace in Qemu 7.0.0: + +``` +~/src/tinygo/tinygo$ /bin/lldb qemu-i386 +(lldb) target create "qemu-i386" +Current executable set to 'qemu-i386' (aarch64). +(lldb) run test +Process 98106 launched: '/usr/bin/qemu-i386' (aarch64) +Process 98106 stopped +* thread #1, name = 'qemu-i386', stop reason = signal SIGSEGV: address access protected (fault address: 0x8000) + frame #0: 0x0000aaaaaac4b564 qemu-i386`cpu_ldub_code + 32 +qemu-i386`cpu_ldub_code: +-> 0xaaaaaac4b564 <+32>: ldrb w0, [x0, w1, uxtw] + 0xaaaaaac4b568 <+36>: str xzr, [x2] + 0xaaaaaac4b56c <+40>: ret + +qemu-i386`cpu_lduw_code: + 0xaaaaaac4b570 <+0>: mrs x2, TPIDR_EL0 +(lldb) bt +* thread #1, name = 'qemu-i386', stop reason = signal SIGSEGV: address access protected (fault address: 0x8000) + * frame #0: 0x0000aaaaaac4b564 qemu-i386`cpu_ldub_code + 32 + frame #1: 0x0000aaaaaac4a4a8 qemu-i386`translator_ldub_swap + 72 + frame #2: 0x0000aaaaaabe6714 qemu-i386`___lldb_unnamed_symbol6310 + 144 + frame #3: 0x0000aaaaaabed2e8 qemu-i386`___lldb_unnamed_symbol6311 + 24 + frame #4: 0x0000aaaaaac4a040 qemu-i386`translator_loop + 400 + frame #5: 0x0000aaaaaabed5a8 qemu-i386`gen_intermediate_code + 72 + frame #6: 0x0000aaaaaac486ec qemu-i386`tb_gen_code + 364 + frame #7: 0x0000aaaaaac43068 qemu-i386`cpu_exec + 1480 + frame #8: 0x0000aaaaaabaa4b0 qemu-i386`cpu_loop + 208 + frame #9: 0x0000aaaaaab8cb54 qemu-i386`main + 2020 + frame #10: 0x0000fffff7687b80 libc.so.6`___lldb_unnamed_symbol2945 + 112 + frame #11: 0x0000fffff7687c60 libc.so.6`__libc_start_main + 160 + frame #12: 0x0000aaaaaab8d3b0 qemu-i386`_start + 48 +(lldb) ^D +``` + +And an even better backtrace for an even older version (5.2.0). Though I should note that this GDB also had an assertion failue, but the backtrace looks reasonable: + +``` +#0 0x0000aaaaaaba7804 in cpu_ldub_code (env=env@entry=0x0, ptr=0) at ../../accel/tcg/user-exec.c:1170 +#1 0x0000aaaaaab40d04 in translator_ldub_swap (do_swap=false, pc=<optimized out>, env=<optimized out>) at ./include/exec/translator.h:176 +#2 translator_ldub (pc=<optimized out>, env=<optimized out>) at ./include/exec/translator.h:176 +#3 x86_ldub_code (env=env@entry=0xaaaaaad809f0, s=s@entry=0xffffffffe990) at ../../target/i386/translate.c:1916 +#4 0x0000aaaaaab51670 in disas_insn (s=s@entry=0xffffffffe990, cpu=<optimized out>, cpu=<optimized out>) at ../../target/i386/translate.c:4506 +#5 0x0000aaaaaab5e1c8 in i386_tr_translate_insn (dcbase=0xffffffffe990, cpu=<optimized out>) at ../../target/i386/translate.c:8569 +#6 0x0000aaaaaabbc9f4 in translator_loop (ops=0xaaaaaacd62b0 <i386_tr_ops>, db=0xffffffffe990, cpu=0xaaaaaad786a0, tb=<optimized out>, max_insns=<optimized out>) + at ../../accel/tcg/translator.c:103 +#7 0x0000aaaaaab5e470 in gen_intermediate_code (cpu=cpu@entry=0xaaaaaad786a0, tb=tb@entry=0xffffe8007f00, max_insns=max_insns@entry=512) + at ../../target/i386/translate.c:8631 +#8 0x0000aaaaaabcd54c in tb_gen_code (cpu=cpu@entry=0xaaaaaad786a0, pc=pc@entry=0, cs_base=cs_base@entry=0, flags=flags@entry=4194483, cflags=-16777216, + cflags@entry=0) at ../../accel/tcg/translate-all.c:1744 +#9 0x0000aaaaaabbe2a8 in tb_find (cf_mask=0, tb_exit=0, last_tb=0x0, cpu=0xaaaaaad786a0) at ../../accel/tcg/cpu-exec.c:414 +#10 cpu_exec (cpu=cpu@entry=0xaaaaaad786a0) at ../../accel/tcg/cpu-exec.c:770 +#11 0x0000aaaaaab3a438 in cpu_loop (env=env@entry=0xaaaaaad809f0) at ../../linux-user/i386/cpu_loop.c:207 +#12 0x0000aaaaaab1df00 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at ../../linux-user/main.c:882 +``` |