diff --git a/linker/linker.c b/linker/linker.c index eb9cc3e98..739d3e424 100644 --- a/linker/linker.c +++ b/linker/linker.c @@ -640,10 +640,6 @@ static int open_library(const char *name) return -1; } -/* temporary space for holding the first page of the shared lib - * which contains the elf header (with the pht). */ -static unsigned char __header[PAGE_SIZE]; - typedef struct { long mmap_addr; char tag[4]; /* 'P', 'R', 'E', ' ' */ @@ -1086,29 +1082,34 @@ load_library(const char *name) unsigned ext_sz; unsigned req_base; const char *bname; + struct stat sb; soinfo *si = NULL; - Elf32_Ehdr *hdr; + Elf32_Ehdr *hdr = MAP_FAILED; - if(fd == -1) { + if (fd == -1) { DL_ERR("Library '%s' not found", name); return NULL; } - /* We have to read the ELF header to figure out what to do with this image + /* We have to read the ELF header to figure out what to do with this image. + * Map entire file for this. There won't be much difference in physical + * memory usage or performance. */ - if (lseek(fd, 0, SEEK_SET) < 0) { - DL_ERR("lseek() failed!"); + if (fstat(fd, &sb) < 0) { + DL_ERR("%5d fstat() failed! (%s)", pid, strerror(errno)); goto fail; } - if ((cnt = read(fd, &__header[0], PAGE_SIZE)) < 0) { - DL_ERR("read() failed!"); + hdr = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0); + if (hdr == MAP_FAILED) { + DL_ERR("%5d failed to mmap() header of '%s' (%s)", + pid, name, strerror(errno)); goto fail; } /* Parse the ELF header and get the size of the memory footprint for * the library */ - req_base = get_lib_extents(fd, name, &__header[0], &ext_sz); + req_base = get_lib_extents(fd, name, hdr, &ext_sz); if (req_base == (unsigned)-1) goto fail; TRACE("[ %5d - '%s' (%s) wants base=0x%08x sz=0x%08x ]\n", pid, name, @@ -1138,22 +1139,20 @@ load_library(const char *name) pid, name, (void *)si->base, (unsigned) ext_sz); /* Now actually load the library's segments into right places in memory */ - if (load_segments(fd, &__header[0], si) < 0) { + if (load_segments(fd, hdr, si) < 0) { goto fail; } - /* this might not be right. Technically, we don't even need this info - * once we go through 'load_segments'. */ - hdr = (Elf32_Ehdr *)si->base; si->phdr = (Elf32_Phdr *)((unsigned char *)si->base + hdr->e_phoff); si->phnum = hdr->e_phnum; - /**/ + munmap(hdr, sb.st_size); close(fd); return si; fail: if (si) free_info(si); + if (hdr != MAP_FAILED) munmap(hdr, sb.st_size); close(fd); return NULL; } @@ -1678,7 +1677,7 @@ static int link_image(soinfo *si, unsigned wr_offset) if (si->flags & (FLAG_EXE | FLAG_LINKER)) { /* Locate the needed program segments (DYNAMIC/ARM_EXIDX) for - * linkage info if this is the executable or the linker itself. + * linkage info if this is the executable or the linker itself. * If this was a dynamic lib, that would have been done at load time. * * TODO: It's unfortunate that small pieces of this are