| Message ID | 1282938463-26450-1-git-send-email-julia@diku.dk |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Julia Lawall <julia@diku.dk> Date: Fri, 27 Aug 2010 21:47:43 +0200 > The string clone is only used as a temporary copy of the argument val > within the while loop, and so it should be freed before leaving the > function. The call to strsep, however, modifies clone, so a pointer to the > front of the string is kept in saved_clone, to make it possible to free it. > > The sematic match that finds this problem is as follows: > (http://coccinelle.lip6.fr/) ... > Signed-off-by: Julia Lawall <julia@diku.dk> Applied, thanks! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c index 0ec9bd0..850c737 100644 --- a/net/ipv4/tcp_cong.c +++ b/net/ipv4/tcp_cong.c @@ -196,10 +196,10 @@ void tcp_get_allowed_congestion_control(char *buf, size_t maxlen) int tcp_set_allowed_congestion_control(char *val) { struct tcp_congestion_ops *ca; - char *clone, *name; + char *saved_clone, *clone, *name; int ret = 0; - clone = kstrdup(val, GFP_USER); + saved_clone = clone = kstrdup(val, GFP_USER); if (!clone) return -ENOMEM; @@ -226,6 +226,7 @@ int tcp_set_allowed_congestion_control(char *val) } out: spin_unlock(&tcp_cong_list_lock); + kfree(saved_clone); return ret; }
The string clone is only used as a temporary copy of the argument val within the while loop, and so it should be freed before leaving the function. The call to strsep, however, modifies clone, so a pointer to the front of the string is kept in saved_clone, to make it possible to free it. The sematic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r exists@ local idexpression x; expression E; identifier l; statement S; @@ *x= \(kasprintf\|kstrdup\)(...); ... if (x == NULL) S ... when != kfree(x) when != E = x if (...) { <... when != kfree(x) * goto l; ...> * return ...; } // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> --- net/ipv4/tcp_cong.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html