--- uClibc-0.9.29.oorig/test/mmap/mmap2.c	(revision 0)

+++ uClibc-0.9.29/test/mmap/mmap2.c	(revision 18616)

@@ -0,0 +1,41 @@

+/* When trying to map /dev/mem with offset 0xFFFFF000 on the ARM platform, mmap

+ * returns -EOVERFLOW.

+ *

+ * Since off_t is defined as a long int and the sign bit is set in the address,

+ * the shift operation shifts in ones instead of zeroes

+ * from the left. This results the offset sent to the kernel function becomes

+ * 0xFFFFFFFF instead of 0x000FFFFF with MMAP2_PAGE_SHIFT set to 12.

+ */

+

+#include <unistd.h>

+#include <stdio.h>

+#include <stdlib.h>

+#include <string.h>

+#include <errno.h>

+#include <fcntl.h>

+#include <sys/mman.h>

+

+#define FATAL do { fprintf(stderr, "Error at line %d, file %s (%d) [%s]\n", \

+  __LINE__, __FILE__, errno, strerror(errno)); exit(1); } while(0)

+

+#define MAP_SIZE 4096UL

+#define MAP_MASK (MAP_SIZE - 1)

+

+int main(int argc, char **argv) {

+    void* map_base = 0;

+    int fd;

+    off_t target = 0xfffff000;

+    if((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1) FATAL;

+    printf("/dev/mem opened.\n");

+    fflush(stdout);

+

+   /* Map one page */

+    map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED,

+                        fd, target & ~MAP_MASK);

+    if(map_base == (void *) -1) FATAL;

+    printf("Memory mapped at address %p.\n", map_base);

+    fflush(stdout);

+    if(munmap(map_base, MAP_SIZE) == -1) FATAL;

+    close(fd);

+    return 0;

+}

--- uClibc-0.9.29.oorig/libc/sysdeps/linux/arm/mmap.c	(revision 18615)

+++ uClibc-0.9.29/libc/sysdeps/linux/arm/mmap.c	(revision 18616)

@@ -27,7 +27,6 @@ __ptr_t mmap(__ptr_t addr, size_t len, i

 #elif defined  (__NR_mmap2)

 #define __NR__mmap __NR_mmap2

-

 #ifndef MMAP2_PAGE_SHIFT

 # define MMAP2_PAGE_SHIFT 12

 #endif

@@ -39,9 +38,17 @@ __ptr_t mmap(__ptr_t addr, size_t len, i

 {

   /* check if offset is page aligned */

     if (offset & ((1 << MMAP2_PAGE_SHIFT) - 1))

+    {

+        __set_errno(EINVAL);

         return MAP_FAILED;

+    }

+#ifdef __USE_FILE_OFFSET64

+  return (__ptr_t) _mmap (addr, len, prot, flags,

+						  fd,((__u_quad_t) offset >> MMAP2_PAGE_SHIFT));

+#else

   return (__ptr_t) _mmap (addr, len, prot, flags,

-						  fd,(off_t) (offset >> MMAP2_PAGE_SHIFT));

+                          fd,((__u_long) offset >> MMAP2_PAGE_SHIFT));

+#endif

 }

 #elif defined (__NR_mmap)

 # define __NR__mmap __NR_mmap

--- uClibc-0.9.29.oorig/libc/sysdeps/linux/common/mmap64.c	(revision 18615)

+++ uClibc-0.9.29/libc/sysdeps/linux/common/mmap64.c	(revision 18616)

@@ -58,8 +58,13 @@ __ptr_t mmap64(__ptr_t addr, size_t len,

 		__set_errno(EINVAL);

 		return MAP_FAILED;

 	}

-

-	return __syscall_mmap2(addr, len, prot, flags, fd, (off_t) (offset >> MMAP2_PAGE_SHIFT));

+#ifdef __USE_FILE_OFFSET64

+  return __syscall_mmap2(addr, len, prot, flags,

+                         fd,((__u_quad_t)offset >> MMAP2_PAGE_SHIFT));

+#else

+   return __syscall_mmap2(addr, len, prot, flags,

+                          fd,((__u_long)offset >> MMAP2_PAGE_SHIFT));

+#endif

 }

 # endif