[CVE-2009-0029] System call wrapper special cases

System calls with an unsigned long long argument can't be converted with
the standard wrappers since that would include a cast to long, which in
turn means that we would lose the upper 32 bit on 32 bit architectures.
Also semctl can't use the standard wrapper since it has a 'union'
parameter.

So we handle them as special case and add some extra wrappers instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

1 files changed, 20 insertions, 4 deletions

diff --git a/fs/read_write.c b/fs/read_write.c
index 940367f51f2a..7a8326bc5903 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -403,8 +403,8 @@ asmlinkage long sys_write(unsigned int fd, const char __user * buf, size_t count
         return ret;
 }
 
-asmlinkage long sys_pread64(unsigned int fd, char __user *buf,
-                             size_t count, loff_t pos)
+SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf,
+                        size_t count, loff_t pos)
 {
         struct file *file;
         ssize_t ret = -EBADF;
@@ -423,9 +423,17 @@ asmlinkage long sys_pread64(unsigned int fd, char __user *buf,
 
         return ret;
 }
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+asmlinkage long SyS_pread64(long fd, long buf, long count, loff_t pos)
+{
+        return SYSC_pread64((unsigned int) fd, (char __user *) buf,
+                            (size_t) count, pos);
+}
+SYSCALL_ALIAS(sys_pread64, SyS_pread64);
+#endif
 
-asmlinkage long sys_pwrite64(unsigned int fd, const char __user *buf,
-                              size_t count, loff_t pos)
+SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf,
+                         size_t count, loff_t pos)
 {
         struct file *file;
         ssize_t ret = -EBADF;
@@ -444,6 +452,14 @@ asmlinkage long sys_pwrite64(unsigned int fd, const char __user *buf,
 
         return ret;
 }
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+asmlinkage long SyS_pwrite64(long fd, long buf, long count, loff_t pos)
+{
+        return SYSC_pwrite64((unsigned int) fd, (const char __user *) buf,
+                             (size_t) count, pos);
+}
+SYSCALL_ALIAS(sys_pwrite64, SyS_pwrite64);
+#endif
 
 /*
  * Reduce an iovec's length in-place.  Return the resulting number of segments