diff options
| -rw-r--r-- | elf/dl-load.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/elf/dl-load.c b/elf/dl-load.c index 88ee318aad..5f5791686d 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -28,6 +28,23 @@ Cambridge, MA 02139, USA. */ #include "dynamic-link.h" +/* On some systems, no flag bits are given to specify file mapping. */ +#ifndef MAP_FILE +#define MAP_FILE 0 +#endif + +/* The right way to map in the shared library files is MAP_COPY, which + makes a virtual copy of the data at the time of the mmap call; this + guarantees the mapped pages will be consistent even if the file is + overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we + get is MAP_PRIVATE, which copies each page when it is modified; this + means if the file is overwritten, we may at some point get some pages + from the new version after starting with pages from the old version. */ +#ifndef MAP_COPY +#define MAP_COPY MAP_PRIVATE +#endif + + #include <endian.h> #if BYTE_ORDER == BIG_ENDIAN #define byteorder ELFDATA2MSB @@ -182,7 +199,7 @@ _dl_map_object_from_fd (const char *name, int fd, char *realname) int prot, int fixed, off_t offset) { caddr_t mapat = mmap ((caddr_t) mapstart, len, prot, - fixed|MAP_COPY|MAP_FILE|MAP_INHERIT, + fixed|MAP_COPY|MAP_FILE, fd, offset); if (mapat == (caddr_t) -1) lose (errno, "failed to map segment from shared object"); @@ -390,10 +407,10 @@ _dl_map_object_from_fd (const char *name, int fd, char *realname) /* Map the remaining zero pages in from the zero fill FD. */ caddr_t mapat; mapat = mmap ((caddr_t) zeropage, zeroend - zeropage, c->prot, - MAP_ANON|MAP_PRIVATE|MAP_FIXED|MAP_INHERIT, + MAP_ANON|MAP_PRIVATE|MAP_FIXED, _dl_zerofd, 0); if (mapat == (caddr_t) -1) - lose (errno, "cannot map zero pages"); + lose (errno, "cannot map zero-fill pages"); } } @@ -401,6 +418,9 @@ _dl_map_object_from_fd (const char *name, int fd, char *realname) } } + if (type == ET_EXEC) + l->l_type = lt_executable; + if (l->l_ld == 0) { if (type == ET_DYN) |