[Qemu-devel] [PATCH RFC v3 6/7] qemu_thread_join: fix segmentation fault

Fei Li posted 7 patches 7 years, 4 months ago
There is a newer version of this series
[Qemu-devel] [PATCH RFC v3 6/7] qemu_thread_join: fix segmentation fault
Posted by Fei Li 7 years, 4 months ago
To avoid the segmentation fault in qemu_thread_join(), just directly
return when the QemuThread *thread was failed to be created in both
qemu-thread-posix.c and qemu-thread-win32.c.

Signed-off-by: Fei Li <fli@suse.com>
---
 util/qemu-thread-posix.c | 3 +++
 util/qemu-thread-win32.c | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
index dfa66ff2fb..289af4fab5 100644
--- a/util/qemu-thread-posix.c
+++ b/util/qemu-thread-posix.c
@@ -562,6 +562,9 @@ void *qemu_thread_join(QemuThread *thread)
     int err;
     void *ret;
 
+    if (!thread->thread) {
+        return NULL;
+    }
     err = pthread_join(thread->thread, &ret);
     if (err) {
         error_exit(err, __func__);
diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c
index 4a363ca675..1a27e1cf6f 100644
--- a/util/qemu-thread-win32.c
+++ b/util/qemu-thread-win32.c
@@ -366,7 +366,7 @@ void *qemu_thread_join(QemuThread *thread)
     HANDLE handle;
 
     data = thread->data;
-    if (data->mode == QEMU_THREAD_DETACHED) {
+    if (data == NULL || data->mode == QEMU_THREAD_DETACHED) {
         return NULL;
     }
 
-- 
2.13.7


Re: [Qemu-devel] [PATCH RFC v3 6/7] qemu_thread_join: fix segmentation fault
Posted by Fam Zheng 7 years, 4 months ago
On Wed, 09/19 21:35, Fei Li wrote:
> To avoid the segmentation fault in qemu_thread_join(), just directly
> return when the QemuThread *thread was failed to be created in both
> qemu-thread-posix.c and qemu-thread-win32.c.

Per English grammar, I think "when the QemuThread *thread failed to be created
in either qemu-thread-posix.c or qemu-thread-win32.c" sounds better.

> 
> Signed-off-by: Fei Li <fli@suse.com>
> ---
>  util/qemu-thread-posix.c | 3 +++
>  util/qemu-thread-win32.c | 2 +-
>  2 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
> index dfa66ff2fb..289af4fab5 100644
> --- a/util/qemu-thread-posix.c
> +++ b/util/qemu-thread-posix.c
> @@ -562,6 +562,9 @@ void *qemu_thread_join(QemuThread *thread)
>      int err;
>      void *ret;
>  
> +    if (!thread->thread) {
> +        return NULL;
> +    }
>      err = pthread_join(thread->thread, &ret);
>      if (err) {
>          error_exit(err, __func__);
> diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c
> index 4a363ca675..1a27e1cf6f 100644
> --- a/util/qemu-thread-win32.c
> +++ b/util/qemu-thread-win32.c
> @@ -366,7 +366,7 @@ void *qemu_thread_join(QemuThread *thread)
>      HANDLE handle;
>  
>      data = thread->data;
> -    if (data->mode == QEMU_THREAD_DETACHED) {
> +    if (data == NULL || data->mode == QEMU_THREAD_DETACHED) {
>          return NULL;
>      }
>  
> -- 
> 2.13.7
> 

Reviewed-by: Fam Zheng <famz@redhat.com>


Re: [Qemu-devel] [PATCH RFC v3 6/7] qemu_thread_join: fix segmentation fault
Posted by Fei Li 7 years, 4 months ago

On 09/19/2018 11:14 PM, Fam Zheng wrote:
> On Wed, 09/19 21:35, Fei Li wrote:
>> To avoid the segmentation fault in qemu_thread_join(), just directly
>> return when the QemuThread *thread was failed to be created in both
>> qemu-thread-posix.c and qemu-thread-win32.c.
> Per English grammar, I think "when the QemuThread *thread failed to be created
> in either qemu-thread-posix.c or qemu-thread-win32.c" sounds better.
Thanks for the comment, much better. :)

Have a nice day
Fei
>
>> Signed-off-by: Fei Li <fli@suse.com>
>> ---
>>   util/qemu-thread-posix.c | 3 +++
>>   util/qemu-thread-win32.c | 2 +-
>>   2 files changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
>> index dfa66ff2fb..289af4fab5 100644
>> --- a/util/qemu-thread-posix.c
>> +++ b/util/qemu-thread-posix.c
>> @@ -562,6 +562,9 @@ void *qemu_thread_join(QemuThread *thread)
>>       int err;
>>       void *ret;
>>   
>> +    if (!thread->thread) {
>> +        return NULL;
>> +    }
>>       err = pthread_join(thread->thread, &ret);
>>       if (err) {
>>           error_exit(err, __func__);
>> diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c
>> index 4a363ca675..1a27e1cf6f 100644
>> --- a/util/qemu-thread-win32.c
>> +++ b/util/qemu-thread-win32.c
>> @@ -366,7 +366,7 @@ void *qemu_thread_join(QemuThread *thread)
>>       HANDLE handle;
>>   
>>       data = thread->data;
>> -    if (data->mode == QEMU_THREAD_DETACHED) {
>> +    if (data == NULL || data->mode == QEMU_THREAD_DETACHED) {
>>           return NULL;
>>       }
>>   
>> -- 
>> 2.13.7
>>
> Reviewed-by: Fam Zheng <famz@redhat.com>
>
>
>
>