* [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy()
@ 2015-08-07 13:51 Andrew Cooper
2015-08-07 14:22 ` Wei Liu
2015-08-13 9:45 ` Wei Liu
0 siblings, 2 replies; 4+ messages in thread
From: Andrew Cooper @ 2015-08-07 13:51 UTC (permalink / raw)
To: Xen-devel; +Cc: Andrew Cooper, Ian Jackson, Ian Campbell, Wei Liu
C requires that every use of va_copy() is matched with a va_end() call.
This is especially important for x86_64 as va_{start,copy}() may need to
allocate memory to generate a va_list containing parameters which were
previously in registers.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
---
tools/xenstore/talloc.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/tools/xenstore/talloc.c b/tools/xenstore/talloc.c
index 54dbd02..d7edcf3 100644
--- a/tools/xenstore/talloc.c
+++ b/tools/xenstore/talloc.c
@@ -1101,13 +1101,16 @@ char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
/* this call looks strange, but it makes it work on older solaris boxes */
if ((len = vsnprintf(&c, 1, fmt, ap2)) < 0) {
+ va_end(ap2);
return NULL;
}
+ va_end(ap2);
ret = _talloc(t, len+1);
if (ret) {
VA_COPY(ap2, ap);
vsnprintf(ret, len+1, fmt, ap2);
+ va_end(ap2);
talloc_set_name_const(ret, ret);
}
@@ -1161,8 +1164,10 @@ static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
* the original string. Most current callers of this
* function expect it to never return NULL.
*/
+ va_end(ap2);
return s;
}
+ va_end(ap2);
s = talloc_realloc(NULL, s, char, s_len + len+1);
if (!s) return NULL;
@@ -1170,6 +1175,7 @@ static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
VA_COPY(ap2, ap);
vsnprintf(s+s_len, len+1, fmt, ap2);
+ va_end(ap2);
talloc_set_name_const(s, s);
return s;
--
1.7.10.4
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy()
2015-08-07 13:51 [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy() Andrew Cooper
@ 2015-08-07 14:22 ` Wei Liu
2015-08-13 9:45 ` Wei Liu
1 sibling, 0 replies; 4+ messages in thread
From: Wei Liu @ 2015-08-07 14:22 UTC (permalink / raw)
To: Andrew Cooper; +Cc: Wei Liu, Ian Jackson, Ian Campbell, Xen-devel
On Fri, Aug 07, 2015 at 02:51:59PM +0100, Andrew Cooper wrote:
> C requires that every use of va_copy() is matched with a va_end() call.
>
> This is especially important for x86_64 as va_{start,copy}() may need to
> allocate memory to generate a va_list containing parameters which were
> previously in registers.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
This is a candidate for backport.
> ---
> CC: Ian Campbell <Ian.Campbell@citrix.com>
> CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
> CC: Wei Liu <wei.liu2@citrix.com>
> ---
> tools/xenstore/talloc.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/tools/xenstore/talloc.c b/tools/xenstore/talloc.c
> index 54dbd02..d7edcf3 100644
> --- a/tools/xenstore/talloc.c
> +++ b/tools/xenstore/talloc.c
> @@ -1101,13 +1101,16 @@ char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
>
> /* this call looks strange, but it makes it work on older solaris boxes */
> if ((len = vsnprintf(&c, 1, fmt, ap2)) < 0) {
> + va_end(ap2);
> return NULL;
> }
> + va_end(ap2);
>
> ret = _talloc(t, len+1);
> if (ret) {
> VA_COPY(ap2, ap);
> vsnprintf(ret, len+1, fmt, ap2);
> + va_end(ap2);
> talloc_set_name_const(ret, ret);
> }
>
> @@ -1161,8 +1164,10 @@ static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
> * the original string. Most current callers of this
> * function expect it to never return NULL.
> */
> + va_end(ap2);
> return s;
> }
> + va_end(ap2);
>
> s = talloc_realloc(NULL, s, char, s_len + len+1);
> if (!s) return NULL;
> @@ -1170,6 +1175,7 @@ static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
> VA_COPY(ap2, ap);
>
> vsnprintf(s+s_len, len+1, fmt, ap2);
> + va_end(ap2);
> talloc_set_name_const(s, s);
>
> return s;
> --
> 1.7.10.4
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy()
2015-08-07 13:51 [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy() Andrew Cooper
2015-08-07 14:22 ` Wei Liu
@ 2015-08-13 9:45 ` Wei Liu
2015-08-13 10:31 ` Ian Campbell
1 sibling, 1 reply; 4+ messages in thread
From: Wei Liu @ 2015-08-13 9:45 UTC (permalink / raw)
To: Andrew Cooper; +Cc: Wei Liu, Ian Jackson, Ian Campbell, Xen-devel
On Fri, Aug 07, 2015 at 02:51:59PM +0100, Andrew Cooper wrote:
> C requires that every use of va_copy() is matched with a va_end() call.
>
> This is especially important for x86_64 as va_{start,copy}() may need to
> allocate memory to generate a va_list containing parameters which were
> previously in registers.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
> ---
> CC: Ian Campbell <Ian.Campbell@citrix.com>
> CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
> CC: Wei Liu <wei.liu2@citrix.com>
> ---
> tools/xenstore/talloc.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/tools/xenstore/talloc.c b/tools/xenstore/talloc.c
> index 54dbd02..d7edcf3 100644
> --- a/tools/xenstore/talloc.c
> +++ b/tools/xenstore/talloc.c
> @@ -1101,13 +1101,16 @@ char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
>
> /* this call looks strange, but it makes it work on older solaris boxes */
> if ((len = vsnprintf(&c, 1, fmt, ap2)) < 0) {
> + va_end(ap2);
> return NULL;
> }
> + va_end(ap2);
>
> ret = _talloc(t, len+1);
> if (ret) {
> VA_COPY(ap2, ap);
> vsnprintf(ret, len+1, fmt, ap2);
> + va_end(ap2);
> talloc_set_name_const(ret, ret);
> }
>
> @@ -1161,8 +1164,10 @@ static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
> * the original string. Most current callers of this
> * function expect it to never return NULL.
> */
> + va_end(ap2);
> return s;
> }
> + va_end(ap2);
>
> s = talloc_realloc(NULL, s, char, s_len + len+1);
> if (!s) return NULL;
> @@ -1170,6 +1175,7 @@ static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
> VA_COPY(ap2, ap);
>
> vsnprintf(s+s_len, len+1, fmt, ap2);
> + va_end(ap2);
> talloc_set_name_const(s, s);
>
> return s;
> --
> 1.7.10.4
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy()
2015-08-13 9:45 ` Wei Liu
@ 2015-08-13 10:31 ` Ian Campbell
0 siblings, 0 replies; 4+ messages in thread
From: Ian Campbell @ 2015-08-13 10:31 UTC (permalink / raw)
To: Wei Liu, Andrew Cooper; +Cc: Ian Jackson, Xen-devel
On Thu, 2015-08-13 at 10:45 +0100, Wei Liu wrote:
> On Fri, Aug 07, 2015 at 02:51:59PM +0100, Andrew Cooper wrote:
> > C requires that every use of va_copy() is matched with a va_end() call.
> >
> > This is especially important for x86_64 as va_{start,copy}() may need
> > to
> > allocate memory to generate a va_list containing parameters which were
> > previously in registers.
> >
> > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
>
> Release-acked-by: Wei Liu <wei.liu2@citrix.com>
Applied, thanks.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2015-08-13 10:31 UTC | newest]
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2015-08-07 13:51 [PATCH for-4.6] tools/xenstore: Correct use of va_end() after va_copy() Andrew Cooper
2015-08-07 14:22 ` Wei Liu
2015-08-13 9:45 ` Wei Liu
2015-08-13 10:31 ` Ian Campbell
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