提交 8d96b106 编写于 作者: N NeilBrown 提交者: Trond Myklebust

NFS: fix bug in legacy DNS resolver.

The DNS resolver's use of the sunrpc cache involves a 'ttl' number
(relative) rather that a timeout (absolute).  This confused me when
I wrote
  commit c5b29f88
     "sunrpc: use seconds since boot in expiry cache"

and I managed to break it.  The effect is that any TTL is interpreted
as 0, and nothing useful gets into the cache.

This patch removes the use of get_expiry() - which really expects an
expiry time - and uses get_uint() instead, treating the int correctly
as a ttl.

This fixes a regression that has been present since 2.6.37, causing
certain NFS accesses in certain environments to incorrectly fail.
Reported-by: NChuck Lever <chuck.lever@oracle.com>
Tested-by: NChuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
上级 2b1bc308
......@@ -217,7 +217,7 @@ static int nfs_dns_parse(struct cache_detail *cd, char *buf, int buflen)
{
char buf1[NFS_DNS_HOSTNAME_MAXLEN+1];
struct nfs_dns_ent key, *item;
unsigned long ttl;
unsigned int ttl;
ssize_t len;
int ret = -EINVAL;
......@@ -240,7 +240,8 @@ static int nfs_dns_parse(struct cache_detail *cd, char *buf, int buflen)
key.namelen = len;
memset(&key.h, 0, sizeof(key.h));
ttl = get_expiry(&buf);
if (get_uint(&buf, &ttl) < 0)
goto out;
if (ttl == 0)
goto out;
key.h.expiry_time = ttl + seconds_since_boot();
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册