[PATCH v2] setrlimit/getrlimit: Use __nonnull to avoid null pointer

[Xiaoming Ni]

Add __nonnull((2)) to the setrlimit()/getrlimit() function declaration
to avoid null pointer access.

-----
v2
  According to the suggestions of the Adhemerval Zanella and Zack Weinberg:
    use __nonnull() to check null pointers in the compilation phase.
    do not add pointer check code to setrlimit()/getrlimit().
    The validity of the "resource" parameter is checked in the syscall.
v1
  https://public-inbox.org/libc-alpha/20201230114131.47589-1-nixiaoming@huawei.com/
-----
---
 include/sys/resource.h  |  4 ++--
 resource/sys/resource.h | 14 ++++++++------
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/include/sys/resource.h b/include/sys/resource.h
index 2235b020fc..21d3908714 100644
--- a/include/sys/resource.h
+++ b/include/sys/resource.h
@@ -126,13 +126,13 @@ libc_hidden_proto (__getrlimit64);
 
 /* Now define the internal interfaces.  */
 extern int __getrlimit (enum __rlimit_resource __resource,
-			struct rlimit *__rlimits);
+			struct rlimit *__rlimits) __nonnull ((2));
 libc_hidden_proto (__getrlimit)
 extern int __getrusage (enum __rusage_who __who, struct rusage *__usage)
 	attribute_hidden;
 
 extern int __setrlimit (enum __rlimit_resource __resource,
-			const struct rlimit *__rlimits);
+			const struct rlimit *__rlimits) __nonnull ((2));
 libc_hidden_proto (__setrlimit);
 
 #if __TIMESIZE == 64
diff --git a/resource/sys/resource.h b/resource/sys/resource.h
index 4edafb50d5..41aa42daa4 100644
--- a/resource/sys/resource.h
+++ b/resource/sys/resource.h
@@ -48,18 +48,19 @@ typedef int __priority_which_t;
    Returns 0 if successful, -1 if not (and sets errno).  */
 #ifndef __USE_FILE_OFFSET64
 extern int getrlimit (__rlimit_resource_t __resource,
-		      struct rlimit *__rlimits) __THROW;
+		      struct rlimit *__rlimits) __THROW __nonnull ((2));
 #else
 # ifdef __REDIRECT_NTH
 extern int __REDIRECT_NTH (getrlimit, (__rlimit_resource_t __resource,
-				       struct rlimit *__rlimits), getrlimit64);
+				       struct rlimit *__rlimits), getrlimit64)
+				       __nonnull ((2));
 # else
 #  define getrlimit getrlimit64
 # endif
 #endif
 #ifdef __USE_LARGEFILE64
 extern int getrlimit64 (__rlimit_resource_t __resource,
-			struct rlimit64 *__rlimits) __THROW;
+			struct rlimit64 *__rlimits) __THROW __nonnull ((2));
 #endif
 
 /* Set the soft and hard limits for RESOURCE to *RLIMITS.
@@ -67,19 +68,20 @@ extern int getrlimit64 (__rlimit_resource_t __resource,
    Return 0 if successful, -1 if not (and sets errno).  */
 #ifndef __USE_FILE_OFFSET64
 extern int setrlimit (__rlimit_resource_t __resource,
-		      const struct rlimit *__rlimits) __THROW;
+		      const struct rlimit *__rlimits) __THROW __nonnull ((2));
 #else
 # ifdef __REDIRECT_NTH
 extern int __REDIRECT_NTH (setrlimit, (__rlimit_resource_t __resource,
 				       const struct rlimit *__rlimits),
-			   setrlimit64);
+			   setrlimit64) __nonnull ((2));
 # else
 #  define setrlimit setrlimit64
 # endif
 #endif
 #ifdef __USE_LARGEFILE64
 extern int setrlimit64 (__rlimit_resource_t __resource,
-			const struct rlimit64 *__rlimits) __THROW;
+			const struct rlimit64 *__rlimits) __THROW
+			__nonnull ((2));
 #endif
 
 /* Return resource usage information on process indicated by WHO
-- 
2.27.0