[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PULL 11/12] linux-user: Add strace support for printing arguments o
From: |
Laurent Vivier |
Subject: |
Re: [PULL 11/12] linux-user: Add strace support for printing arguments of ioctl() |
Date: |
Thu, 9 Jul 2020 17:28:34 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 |
Le 09/07/2020 à 17:20, Peter Maydell a écrit :
> On Sat, 4 Jul 2020 at 17:36, Laurent Vivier <laurent@vivier.eu> wrote:
>>
>> From: Filip Bozuta <Filip.Bozuta@syrmia.com>
>>
>> This patch implements functionality for strace argument printing for ioctls.
>
> Hi; Coverity points out some issues in this change:
>
>
>> +#ifdef TARGET_NR_ioctl
>> +static void
>> +print_syscall_ret_ioctl(const struct syscallname *name, abi_long ret,
>> + abi_long arg0, abi_long arg1, abi_long arg2,
>> + abi_long arg3, abi_long arg4, abi_long arg5)
>> +{
>> + print_syscall_err(ret);
>> +
>> + if (ret >= 0) {
>> + qemu_log(TARGET_ABI_FMT_ld, ret);
>> +
>> + const IOCTLEntry *ie;
>> + const argtype *arg_type;
>> + void *argptr;
>> + int target_size;
>> +
>> + for (ie = ioctl_entries; ie->target_cmd != 0; ie++) {
>> + if (ie->target_cmd == arg1) {
>> + break;
>> + }
>> + }
>> +
>> + if (ie->target_cmd == arg1 &&
>> + (ie->access == IOC_R || ie->access == IOC_RW)) {
>> + arg_type = ie->arg_type;
>> + qemu_log(" (");
>> + arg_type++;
>> + target_size = thunk_type_size(arg_type, 0);
>> + argptr = lock_user(VERIFY_READ, arg2, target_size, 1);
>
> Here we fail to check that lock_user() didn't return NULL...
>
>> + thunk_print(argptr, arg_type);
>
> ...which would cause a segfault in thunk_print().
> This is CID 1430271.
>
>> + unlock_user(argptr, arg2, target_size);
>> + qemu_log(")");
>> + }
>> + }
>> + qemu_log("\n");
>> +}
>> +#endif
>
>> +#ifdef TARGET_NR_ioctl
>> +static void
>> +print_ioctl(const struct syscallname *name,
>> + abi_long arg0, abi_long arg1, abi_long arg2,
>> + abi_long arg3, abi_long arg4, abi_long arg5)
>> +{
>
>> + case TYPE_PTR:
>> + switch (ie->access) {
>> + case IOC_R:
>> + print_pointer(arg2, 1);
>> + break;
>> + case IOC_W:
>> + case IOC_RW:
>> + arg_type++;
>> + target_size = thunk_type_size(arg_type, 0);
>> + argptr = lock_user(VERIFY_READ, arg2, target_size, 1);
>> + thunk_print(argptr, arg_type);
>
> Similarly here we need to check that lock_user didn't fail.
> This is CID 1430272.
>
>> + unlock_user(argptr, arg2, target_size);
>> + break;
>> + }
>> + break;
>> + default:
>> + g_assert_not_reached();
>> + }
>> + }
>> + }
>> + print_syscall_epilogue(name);
>> +}
Thank you Peter.
I fix that.
Laurent
- [PULL 01/12] target/sparc: Translate flushw opcode, (continued)
- [PULL 01/12] target/sparc: Translate flushw opcode, Laurent Vivier, 2020/07/04
- [PULL 02/12] linux-user/sparc64: Fix the handling of window spill trap, Laurent Vivier, 2020/07/04
- [PULL 06/12] linux-user: Add strace support for printing argument of syscalls used for extended attributes, Laurent Vivier, 2020/07/04
- [PULL 04/12] linux-user: Extend strace support to enable argument printing after syscall execution, Laurent Vivier, 2020/07/04
- [PULL 07/12] linux-user: Add strace support for printing arguments of lseek(), Laurent Vivier, 2020/07/04
- [PULL 05/12] linux-user: Add strace support for a group of syscalls, Laurent Vivier, 2020/07/04
- [PULL 12/12] MAINTAINERS: update linux-user maintainer, Laurent Vivier, 2020/07/04
- [PULL 10/12] linux-user: Add thunk argument types for SIOCGSTAMP and SIOCGSTAMPNS, Laurent Vivier, 2020/07/04
- [PULL 11/12] linux-user: Add strace support for printing arguments of ioctl(), Laurent Vivier, 2020/07/04
- [PULL 08/12] linux-user: Add strace support for printing arguments of chown()/lchown(), Laurent Vivier, 2020/07/04
- [PULL 09/12] linux-user: Add strace support for printing arguments of fallocate(), Laurent Vivier, 2020/07/04
- [PULL 03/12] linux-user: syscall: ioctls: support DRM_IOCTL_VERSION, Laurent Vivier, 2020/07/04
- Re: [PULL 00/12] Linux user for 5.1 patches, no-reply, 2020/07/04
- Re: [PULL 00/12] Linux user for 5.1 patches, no-reply, 2020/07/04
- Re: [PULL 00/12] Linux user for 5.1 patches, Peter Maydell, 2020/07/07