Re: [PATCH] dns_resolver: assure that dns_query() result is null-terminated

LOL, that was stupid!
Sorry, I'll send a corrected version in a second...

On Sa, 2014-06-07 at 14:54 -0400, Trond Myklebust wrote:

On Sat, Jun 7, 2014 at 1:56 PM, Manuel Schölling
[off-list ref] wrote:

quoted

dns_query() credulously assumes that keys are null-terminated and
returns a copy of a memory block that is off by one.
---
 net/dns_resolver/dns_query.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index e7b6d53..53be635 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c

@@ -149,7 +149,9 @@ int dns_query(const char *type, const char *name, size_t namelen,
        if (!*_result)
                goto put;

-       memcpy(*_result, upayload->data, len + 1);
+       memcpy(*_result, upayload->data, len);
+       *_result[len+1] = '\0';

Off by one...

quoted

+
        if (_expiry)
                *_expiry = rkey->expiry;

--
1.7.10.4

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