commit 7e91ef9e2cd90baff5948504095974d737e1ee12
author Tim Duesterhus <tim@bastelstu.be> Sat Jan 18 02:04:12 2020 +0100
committer Christopher Faulet <cfaulet@haproxy.com> Mon Jan 20 14:26:21 2020 +0100
tree d4181d375ad2d81612974205ac97671865dbca0b
parent ff6603e7335057bfcb1c374b804c2783a2c65142

BUG/MINOR: dns: Make dns_query_id_seed unsigned

Left shifting of large signed values and negative values is undefined.

In a test script clang's ubsan rightfully complains:

> runtime error: left shift of 1934242336581872173 by 13 places cannot be represented in type 'int64_t' (aka 'long')

This bug was introduced in the initial version of the DNS resolver
in 325137d603aa81bd24cbd8c99d816dd42291daa7. The fix must be backported
to HAProxy 1.6+.

(cherry picked from commit fcac33d0c1138ef22914c3b36518c1df105c9b72)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit bf61c6cd41f59e68221eda04e0e4a10d9fafab48)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>

src/dns.c

diff --git a/src/dns.c b/src/dns.c
index 37263bd..d866ab0 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -54,7 +54,7 @@
 struct list dns_resolvers  = LIST_HEAD_INIT(dns_resolvers);
 struct list dns_srvrq_list = LIST_HEAD_INIT(dns_srvrq_list);
 
-static THREAD_LOCAL int64_t dns_query_id_seed = 0; /* random seed */
+static THREAD_LOCAL uint64_t dns_query_id_seed = 0; /* random seed */
 
 DECLARE_STATIC_POOL(dns_answer_item_pool, "dns_answer_item", sizeof(struct dns_answer_item));
 DECLARE_STATIC_POOL(dns_resolution_pool,  "dns_resolution",  sizeof(struct dns_resolution));