1 files changed, 14 insertions, 1 deletions
diff --git a/kernel/printk.c b/kernel/printk.c
index 38e7d5868d6..9a2264fc42c 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -274,7 +274,20 @@ int do_syslog(int type, char __user *buf, int len, bool from_file)
 	char c;
 	int error = 0;
 
-	error = security_syslog(type, from_file);
+	/*
+	 * If this is from /proc/kmsg we only do the capabilities checks
+	 * at open time.
+	 */
+	if (type == SYSLOG_ACTION_OPEN || !from_file) {
+		if (dmesg_restrict && !capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		if ((type != SYSLOG_ACTION_READ_ALL &&
+		     type != SYSLOG_ACTION_SIZE_BUFFER) &&
+		    !capable(CAP_SYS_ADMIN))
+			return -EPERM;
+	}
+
+	error = security_syslog(type);
 	if (error)
 		return error;