[PATCH v3] Consolidate pthread_attr value validation

[Siddhesh Poyarekar <siddhesh at redhat dot com>]

On Fri, Mar 22, 2013 at 11:22:34AM -0700, Roland McGrath wrote:
> The cases here are simply optimization choices.  Those should be left to
> the compiler.  'inline' is a hint to the compiler about optimization
> choice, though from the GCC documentation it's not clear to me it really
> makes any difference in practice at -O2, but clear that it doesn't make any
> difference at -O3.  Hence it's clear that 'inline' should never be used in
> .c files.  That was the context of the previous discussion but I don't
> think we were clear about the distinction between cases in .c files and
> cases in .h files.

OK, thanks for the clarification.  Here's v3 of the cleanup patch.

Siddhesh

	* pthreadP.h (check_sched_policy_attr): New inline function.
	(check_sched_priority_attr): Likewise.
	(check_stacksize_attr): Likewise.
	(__kernel_cpumask_size, __determine_cpumask_size): Declare
	extern.
	(check_cpuset_attr): New inline function.
	* pthread_attr_setschedparam (__pthread_attr_setschedparam):
	Use check_sched_priority_attr.
	* pthread_attr_setschedpolicy.c
	(__pthread_attr_setschedpolicy): Use check_sched_policy_attr.
	* pthread_attr_setstack.c (__pthread_attr_setstack): Use
	check_stacksize_attr.
	* pthread_attr_setstacksize.c (__pthread_attr_setstacksize):
	Likewise.
	* sysdeps/unix/sysv/linux/pthread_attr_setaffinity.c
	(__pthread_attr_setaffinity_new): Use check_cpuset_attr.

diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h
index 39e930c..a34a889 100644
--- a/nptl/pthreadP.h
+++ b/nptl/pthreadP.h
@@ -31,7 +31,7 @@
 #include <pthread-functions.h>
 #include <atomic.h>
 #include <kernel-features.h>
-
+#include <errno.h>
 
 /* Atomic operations on TLS memory.  */
 #ifndef THREAD_ATOMIC_CMPXCHG_VAL
@@ -591,4 +591,66 @@ extern void __wait_lookup_done (void) attribute_hidden;
 # define USE_REQUEUE_PI(mut) 0
 #endif
 
+/* Returns 0 if POL is a valid scheduling policy.  */
+static inline int
+check_sched_policy_attr (int pol)
+{
+  if (pol == SCHED_OTHER || pol == SCHED_FIFO || pol == SCHED_RR)
+    return 0;
+
+  return EINVAL;
+}
+
+/* Returns 0 if PR is within the accepted range of priority values for
+   the scheduling policy POL or EINVAL otherwise.  */
+static inline int
+check_sched_priority_attr (int pr, int pol)
+{
+  int min = __sched_get_priority_min (pol);
+  int max = __sched_get_priority_max (pol);
+
+  if (min >= 0 && max >= 0 && pr >= min && pr <= max)
+    return 0;
+
+  return EINVAL;
+}
+
+/* Returns 0 if ST is a valid stack size for a thread stack and EINVAL
+   otherwise.  */
+static inline int
+check_stacksize_attr (size_t st)
+{
+  if (st >= PTHREAD_STACK_MIN)
+    return 0;
+
+  return EINVAL;
+}
+
+/* Defined in pthread_setaffinity.c.  */
+extern size_t __kernel_cpumask_size attribute_hidden;
+extern int __determine_cpumask_size (pid_t tid);
+
+/* Returns 0 if CS and SZ are valid values for the cpuset and cpuset size
+   respectively.  Otherwise it returns an error number.  */
+static inline int
+check_cpuset_attr (const cpu_set_t *cs, const size_t sz)
+{
+  if (__kernel_cpumask_size == 0)
+    {
+      int res = __determine_cpumask_size (THREAD_SELF->tid);
+      if (res)
+	return res;
+    }
+
+  /* Check whether the new bitmask has any bit set beyond the
+     last one the kernel accepts.  */
+  for (size_t cnt = __kernel_cpumask_size; cnt < sz; ++cnt)
+    if (((char *) cs)[cnt] != '\0')
+      /* Found a nonzero byte.  This means the user request cannot be
+	 fulfilled.  */
+      return EINVAL;
+
+  return 0;
+}
+
 #endif	/* pthreadP.h */
diff --git a/nptl/pthread_attr_setschedparam.c b/nptl/pthread_attr_setschedparam.c
index ec1a8bd..a167f15 100644
--- a/nptl/pthread_attr_setschedparam.c
+++ b/nptl/pthread_attr_setschedparam.c
@@ -30,11 +30,10 @@ __pthread_attr_setschedparam (attr, param)
   assert (sizeof (*attr) >= sizeof (struct pthread_attr));
   struct pthread_attr *iattr = (struct pthread_attr *) attr;
 
-  int min = sched_get_priority_min (iattr->schedpolicy);
-  int max = sched_get_priority_max (iattr->schedpolicy);
-  if (min == -1 || max == -1
-      || param->sched_priority > max || param->sched_priority < min)
-    return EINVAL;
+  int ret = check_sched_priority_attr (param->sched_priority,
+				       iattr->schedpolicy);
+  if (ret)
+    return ret;
 
   /* Copy the new values.  */
   memcpy (&iattr->schedparam, param, sizeof (struct sched_param));
diff --git a/nptl/pthread_attr_setschedpolicy.c b/nptl/pthread_attr_setschedpolicy.c
index 2fa6921..4fe0b8e 100644
--- a/nptl/pthread_attr_setschedpolicy.c
+++ b/nptl/pthread_attr_setschedpolicy.c
@@ -32,8 +32,9 @@ __pthread_attr_setschedpolicy (attr, policy)
   iattr = (struct pthread_attr *) attr;
 
   /* Catch invalid values.  */
-  if (policy != SCHED_OTHER && policy != SCHED_FIFO && policy != SCHED_RR)
-    return EINVAL;
+  int ret = check_sched_policy_attr (policy);
+  if (ret)
+    return ret;
 
   /* Store the new values.  */
   iattr->schedpolicy = policy;
diff --git a/nptl/pthread_attr_setstack.c b/nptl/pthread_attr_setstack.c
index 783cffe..4bd314e 100644
--- a/nptl/pthread_attr_setstack.c
+++ b/nptl/pthread_attr_setstack.c
@@ -39,8 +39,9 @@ __pthread_attr_setstack (attr, stackaddr, stacksize)
   iattr = (struct pthread_attr *) attr;
 
   /* Catch invalid sizes.  */
-  if (stacksize < PTHREAD_STACK_MIN)
-    return EINVAL;
+  int ret = check_stacksize_attr (stacksize);
+  if (ret)
+    return ret;
 
 #ifdef EXTRA_PARAM_CHECKS
   EXTRA_PARAM_CHECKS;
diff --git a/nptl/pthread_attr_setstacksize.c b/nptl/pthread_attr_setstacksize.c
index b7f2919..585bf08 100644
--- a/nptl/pthread_attr_setstacksize.c
+++ b/nptl/pthread_attr_setstacksize.c
@@ -37,8 +37,9 @@ __pthread_attr_setstacksize (attr, stacksize)
   iattr = (struct pthread_attr *) attr;
 
   /* Catch invalid sizes.  */
-  if (stacksize < PTHREAD_STACK_MIN)
-    return EINVAL;
+  int ret = check_stacksize_attr (stacksize);
+  if (ret)
+    return ret;
 
   iattr->stacksize = stacksize;
 
diff --git a/nptl/sysdeps/unix/sysv/linux/pthread_attr_setaffinity.c b/nptl/sysdeps/unix/sysv/linux/pthread_attr_setaffinity.c
index 8b7a499..b4335c5 100644
--- a/nptl/sysdeps/unix/sysv/linux/pthread_attr_setaffinity.c
+++ b/nptl/sysdeps/unix/sysv/linux/pthread_attr_setaffinity.c
@@ -25,9 +25,6 @@
 #include <shlib-compat.h>
 
 
-/* Defined in pthread_setaffinity.c.  */
-extern size_t __kernel_cpumask_size attribute_hidden;
-extern int __determine_cpumask_size (pid_t tid);
 
 
 int
@@ -47,21 +44,10 @@ __pthread_attr_setaffinity_new (pthread_attr_t *attr, size_t cpusetsize,
     }
   else
     {
-      if (__kernel_cpumask_size == 0)
-	{
-	  int res = __determine_cpumask_size (THREAD_SELF->tid);
-	  if (res != 0)
-	    /* Some serious problem.  */
-	    return res;
-	}
+      int ret = check_cpuset_attr (cpuset, cpusetsize);
 
-      /* Check whether the new bitmask has any bit set beyond the
-	 last one the kernel accepts.  */
-      for (size_t cnt = __kernel_cpumask_size; cnt < cpusetsize; ++cnt)
-	if (((char *) cpuset)[cnt] != '\0')
-	  /* Found a nonzero byte.  This means the user request cannot be
-	     fulfilled.  */
-	  return EINVAL;
+      if (ret)
+        return ret;
 
       if (iattr->cpusetsize != cpusetsize)
 	{