[Cluster-devel] [PATCH dlm/next 3/6] fs: dlm: disallow buffer size below default

[Alexander Aring <aahringo@redhat.com>]

I observed dlm messages cannot below this value delivered from upper
layers. This buffer is used inside the current receive handling to copy a
dlm message into it. However we should not allow sizes below the default
value.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
---
 fs/dlm/config.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/dlm/config.c b/fs/dlm/config.c
index 2b30104a34cef..1734f2e861924 100644
--- a/fs/dlm/config.c
+++ b/fs/dlm/config.c
@@ -166,8 +166,14 @@ static bool dlm_check_zero(unsigned int x)
 	return !x;
 }
 
+#define DEFAULT_BUFFER_SIZE     4096
+static bool dlm_check_buffer_size(unsigned int x)
+{
+	return (x < DEFAULT_BUFFER_SIZE);
+}
+
 CLUSTER_ATTR(tcp_port, dlm_check_zero);
-CLUSTER_ATTR(buffer_size, dlm_check_zero);
+CLUSTER_ATTR(buffer_size, dlm_check_buffer_size);
 CLUSTER_ATTR(rsbtbl_size, dlm_check_zero);
 CLUSTER_ATTR(recover_timer, dlm_check_zero);
 CLUSTER_ATTR(toss_secs, dlm_check_zero);
@@ -897,7 +903,6 @@ int dlm_our_addr(struct sockaddr_storage *addr, int num)
 
 /* Config file defaults */
 #define DEFAULT_TCP_PORT       21064
-#define DEFAULT_BUFFER_SIZE     4096
 #define DEFAULT_RSBTBL_SIZE     1024
 #define DEFAULT_RECOVER_TIMER      5
 #define DEFAULT_TOSS_SECS         10
-- 
2.26.2