| --- 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 |
