[PATCH] lib/message.cc: stale pointer bug (v3)

[PATCH] lib/message.cc: stale pointer bug (v3)

[Vladimir.Marek]

From: Vladimir Marek <vlmarek@volny.cz>

Xapian::TermIterator::operator* returns std::string which is destroyed
as soon as (*i).c_str() finishes. The remembered pointer 'term' then
references invalid memory.

Signed-off-by: Vladimir Marek <vlmarek@volny.cz>
---
 lib/message.cc |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/message.cc b/lib/message.cc
index 8720c1b..c4261e6 100644
--- a/lib/message.cc
+++ b/lib/message.cc
@@ -266,18 +266,18 @@ _notmuch_message_get_term (notmuch_message_t *message,
 			   const char *prefix)
 {
     int prefix_len = strlen (prefix);
-    const char *term = NULL;
     char *value;
 
     i.skip_to (prefix);
 
-    if (i != end)
-	term = (*i).c_str ();
+    if (i == end)
+	return NULL;
 
-    if (!term || strncmp (term, prefix, prefix_len))
+    std::string term = *i;
+    if (strncmp (term.c_str(), prefix, prefix_len))
 	return NULL;
 
-    value = talloc_strdup (message, term + prefix_len);
+    value = talloc_strdup (message, term.c_str() + prefix_len);
 
 #if DEBUG_DATABASE_SANITY
     i++;
-- 
1.7.9.2

Re: [PATCH] lib/message.cc: stale pointer bug (v3)

[Jani Nikula]

LGTM

On Thu, 02 May 2013, Vladimir.Marek@oracle.com wrote:
> From: Vladimir Marek <vlmarek@volny.cz>
>
> Xapian::TermIterator::operator* returns std::string which is destroyed
> as soon as (*i).c_str() finishes. The remembered pointer 'term' then
> references invalid memory.
>
> Signed-off-by: Vladimir Marek <vlmarek@volny.cz>
> ---
>  lib/message.cc |   10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/lib/message.cc b/lib/message.cc
> index 8720c1b..c4261e6 100644
> --- a/lib/message.cc
> +++ b/lib/message.cc
> @@ -266,18 +266,18 @@ _notmuch_message_get_term (notmuch_message_t *message,
>  			   const char *prefix)
>  {
>      int prefix_len = strlen (prefix);
> -    const char *term = NULL;
>      char *value;
>  
>      i.skip_to (prefix);
>  
> -    if (i != end)
> -	term = (*i).c_str ();
> +    if (i == end)
> +	return NULL;
>  
> -    if (!term || strncmp (term, prefix, prefix_len))
> +    std::string term = *i;
> +    if (strncmp (term.c_str(), prefix, prefix_len))
>  	return NULL;
>  
> -    value = talloc_strdup (message, term + prefix_len);
> +    value = talloc_strdup (message, term.c_str() + prefix_len);
>  
>  #if DEBUG_DATABASE_SANITY
>      i++;
> -- 
> 1.7.9.2
>
> _______________________________________________
> notmuch mailing list
> notmuch@notmuchmail.org
> http://notmuchmail.org/mailman/listinfo/notmuch

Re: [PATCH] lib/message.cc: stale pointer bug (v3)

[David Bremner]

Vladimir.Marek@oracle.com writes:

> From: Vladimir Marek <vlmarek@volny.cz>
>
> Xapian::TermIterator::operator* returns std::string which is destroyed
> as soon as (*i).c_str() finishes. The remembered pointer 'term' then
> references invalid memory.

Pushed,

d