7 files changed, 28 insertions, 40 deletions

diff --git a/include/linux/security.h b/include/linux/security.h
index b8246a8df7d2..fd4d55fb8845 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -77,7 +77,6 @@ extern int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
 extern int cap_task_setscheduler(struct task_struct *p);
 extern int cap_task_setioprio(struct task_struct *p, int ioprio);
 extern int cap_task_setnice(struct task_struct *p, int nice);
-extern int cap_syslog(int type, bool from_file);
 extern int cap_vm_enough_memory(struct mm_struct *mm, long pages);
 
 struct msghdr;
@@ -1388,7 +1387,7 @@ struct security_operations {
         int (*sysctl) (struct ctl_table *table, int op);
         int (*quotactl) (int cmds, int type, int id, struct super_block *sb);
         int (*quota_on) (struct dentry *dentry);
-        int (*syslog) (int type, bool from_file);
+        int (*syslog) (int type);
         int (*settime) (struct timespec *ts, struct timezone *tz);
         int (*vm_enough_memory) (struct mm_struct *mm, long pages);
 
@@ -1671,7 +1670,7 @@ int security_real_capable_noaudit(struct task_struct *tsk, int cap);
 int security_sysctl(struct ctl_table *table, int op);
 int security_quotactl(int cmds, int type, int id, struct super_block *sb);
 int security_quota_on(struct dentry *dentry);
-int security_syslog(int type, bool from_file);
+int security_syslog(int type);
 int security_settime(struct timespec *ts, struct timezone *tz);
 int security_vm_enough_memory(long pages);
 int security_vm_enough_memory_mm(struct mm_struct *mm, long pages);
@@ -1901,9 +1900,9 @@ static inline int security_quota_on(struct dentry *dentry)
         return 0;
 }
 
-static inline int security_syslog(int type, bool from_file)
+static inline int security_syslog(int type)
 {
-        return cap_syslog(type, from_file);
+        return 0;
 }
 
 static inline int security_settime(struct timespec *ts, struct timezone *tz)
diff --git a/kernel/printk.c b/kernel/printk.c
index 38e7d5868d60..9a2264fc42ca 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;
 
diff --git a/security/capability.c b/security/capability.c
index 30ae00fbecd5..c773635ca3a0 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -17,6 +17,11 @@ static int cap_sysctl(ctl_table *table, int op)
         return 0;
 }
 
+static int cap_syslog(int type)
+{
+        return 0;
+}
+
 static int cap_quotactl(int cmds, int type, int id, struct super_block *sb)
 {
         return 0;
diff --git a/security/commoncap.c b/security/commoncap.c
index 04b80f9912bf..64c2ed9c9015 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -27,7 +27,6 @@
 #include <linux/sched.h>
 #include <linux/prctl.h>
 #include <linux/securebits.h>
-#include <linux/syslog.h>
 
 /*
  * If a non-root user executes a setuid-root binary in
@@ -884,26 +883,6 @@ error:
 }
 
 /**
- * cap_syslog - Determine whether syslog function is permitted
- * @type: Function requested
- * @from_file: Whether this request came from an open file (i.e. /proc)
- *
- * Determine whether the current process is permitted to use a particular
- * syslog function, returning 0 if permission is granted, -ve if not.
- */
-int cap_syslog(int type, bool from_file)
-{
-        if (type != SYSLOG_ACTION_OPEN && from_file)
-                return 0;
-        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;
-        return 0;
-}
-
-/**
  * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
  * @mm: The VM space in which the new mapping is to be made
  * @pages: The size of the mapping
diff --git a/security/security.c b/security/security.c
index 3ef5e2a7a741..1b798d3df710 100644
--- a/security/security.c
+++ b/security/security.c
@@ -197,9 +197,9 @@ int security_quota_on(struct dentry *dentry)
         return security_ops->quota_on(dentry);
 }
 
-int security_syslog(int type, bool from_file)
+int security_syslog(int type)
 {
-        return security_ops->syslog(type, from_file);
+        return security_ops->syslog(type);
 }
 
 int security_settime(struct timespec *ts, struct timezone *tz)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index d9154cf90ae1..65fa8bf596f5 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1973,14 +1973,10 @@ static int selinux_quota_on(struct dentry *dentry)
         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
 }
 
-static int selinux_syslog(int type, bool from_file)
+static int selinux_syslog(int type)
 {
         int rc;
 
-        rc = cap_syslog(type, from_file);
-        if (rc)
-                return rc;
-
         switch (type) {
         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index bc39f4067af6..489a85afa477 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -157,15 +157,11 @@ static int smack_ptrace_traceme(struct task_struct *ptp)
  *
  * Returns 0 on success, error code otherwise.
  */
-static int smack_syslog(int type, bool from_file)
+static int smack_syslog(int typefrom_file)
 {
-        int rc;
+        int rc = 0;
         char *sp = current_security();
 
-        rc = cap_syslog(type, from_file);
-        if (rc != 0)
-                return rc;
-
         if (capable(CAP_MAC_OVERRIDE))
                 return 0;