linker: improve loadable segment protection.
Use the functions in linker_phdr.c to load the PT_LOAD segments
in memory, and toggle their mapping's writable protection bit
as needed. In particular:
- when loading a library, load the segments then unprotected
them to allow relocations to work.
- when relocating the linker of the executable, unprotect
the segments loaded by the kernel to make relocations work
too.
- after all relocations are done, re-protect the segments,
and apply GNU RELRO protection if needed.
- just before calling the destructors, undo the GNU RELRO
protection.
Change-Id: I50e709f03958204b8d6140c0f51ebe24fe089a1b
diff --git a/linker/linker.c b/linker/linker.c
index a3bc171..e90ac0a 100644
--- a/linker/linker.c
+++ b/linker/linker.c
@@ -697,319 +697,6 @@
}
-/* reserve_mem_region
- *
- * This function reserves a chunk of memory to be used for mapping in
- * a prelinked shared library. We reserve the entire memory region here, and
- * then the rest of the linker will relocate the individual loadable
- * segments into the correct locations within this memory range.
- *
- * Args:
- * si->base: The requested base of the allocation.
- * si->size: The size of the allocation.
- *
- * Returns:
- * -1 on failure, and 0 on success. On success, si->base will contain
- * the virtual address at which the library will be mapped.
- */
-
-static int soinfo_reserve_mem_region(soinfo *si)
-{
- void *base = mmap((void *)si->base, si->size, PROT_NONE,
- MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (base == MAP_FAILED) {
- DL_ERR("%5d can NOT map (%sprelinked) library '%s' at 0x%08x "
- "as requested, will try general pool: %d (%s)",
- pid, (si->base ? "" : "non-"), si->name, si->base,
- errno, strerror(errno));
- return -1;
- } else if (base != (void *)si->base) {
- DL_ERR("OOPS: %5d %sprelinked library '%s' mapped at 0x%08x, "
- "not at 0x%08x", pid, (si->base ? "" : "non-"),
- si->name, (unsigned)base, si->base);
- munmap(base, si->size);
- return -1;
- }
- return 0;
-}
-
-static int soinfo_alloc_mem_region(soinfo *si)
-{
- if (si->base) {
- /* Attempt to mmap a prelinked library. */
- return soinfo_reserve_mem_region(si);
- }
-
- /* This is not a prelinked library, so we use the kernel's default
- allocator.
- */
-
- void *base = mmap(NULL, si->size, PROT_NONE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (base == MAP_FAILED) {
- DL_ERR("%5d mmap of library '%s' failed (%d bytes): %d (%s)\n",
- pid, si->name, si->size,
- errno, strerror(errno));
- return -1;
- }
- si->base = (unsigned) base;
- PRINT("%5d mapped library '%s' to %08x via kernel allocator.\n",
- pid, si->name, si->base);
- return 0;
-}
-
-#define MAYBE_MAP_FLAG(x,from,to) (((x) & (from)) ? (to) : 0)
-#define PFLAGS_TO_PROT(x) (MAYBE_MAP_FLAG((x), PF_X, PROT_EXEC) | \
- MAYBE_MAP_FLAG((x), PF_R, PROT_READ) | \
- MAYBE_MAP_FLAG((x), PF_W, PROT_WRITE))
-/* load_segments
- *
- * This function loads all the loadable (PT_LOAD) segments into memory
- * at their appropriate memory offsets off the base address.
- *
- * Args:
- * fd: Open file descriptor to the library to load.
- * header: Pointer to a header page that contains the ELF header.
- * This is needed since we haven't mapped in the real file yet.
- * si: ptr to soinfo struct describing the shared object.
- *
- * Returns:
- * 0 on success, -1 on failure.
- */
-static int
-soinfo_load_segments(soinfo* si, int fd, const Elf32_Phdr* phdr_table, int phdr_count, Elf32_Addr ehdr_phoff)
-{
- const Elf32_Phdr *phdr = phdr_table;
- const Elf32_Phdr *phdr0 = 0; /* program header for the first LOAD segment */
- Elf32_Addr base;
- int cnt;
- unsigned len;
- Elf32_Addr tmp;
- unsigned char *pbase;
- unsigned char *extra_base;
- unsigned extra_len;
- unsigned total_sz = 0;
-
- si->wrprotect_start = 0xffffffff;
- si->wrprotect_end = 0;
-
- TRACE("[ %5d - Begin loading segments for '%s' @ 0x%08x ]\n",
- pid, si->name, (unsigned)si->base);
-
- for (cnt = 0; cnt < phdr_count; ++cnt, ++phdr) {
-
- if (phdr->p_type == PT_LOAD) {
- phdr0 = phdr;
- /*
- * ELF specification section 2-2.
- *
- * PT_LOAD: "Loadable segment entries in the program
- * header table appear in ascending order, sorted on the
- * p_vaddr member."
- */
- si->load_bias = si->base - PAGE_START(phdr->p_vaddr);
- break;
- }
- }
-
- /* "base" might wrap around UINT32_MAX. */
- base = si->load_bias;
-
- /* Now go through all the PT_LOAD segments and map them into memory
- * at the appropriate locations. */
- phdr = phdr_table;
- for (cnt = 0; cnt < phdr_count; ++cnt, ++phdr) {
- if (phdr->p_type == PT_LOAD) {
- DEBUG_DUMP_PHDR(phdr, "PT_LOAD", pid);
- /* we want to map in the segment on a page boundary */
- tmp = base + PAGE_START(phdr->p_vaddr);
- /* add the # of bytes we masked off above to the total length. */
- len = phdr->p_filesz + PAGE_OFFSET(phdr->p_vaddr);
-
- TRACE("[ %d - Trying to load segment from '%s' @ 0x%08x "
- "(0x%08x). p_vaddr=0x%08x p_offset=0x%08x ]\n", pid, si->name,
- (unsigned)tmp, len, phdr->p_vaddr, phdr->p_offset);
- pbase = mmap((void *)tmp, len, PFLAGS_TO_PROT(phdr->p_flags),
- MAP_PRIVATE | MAP_FIXED, fd,
- PAGE_START(phdr->p_offset));
- if (pbase == MAP_FAILED) {
- DL_ERR("%d failed to map segment from '%s' @ 0x%08x (0x%08x). "
- "p_vaddr=0x%08x p_offset=0x%08x", pid, si->name,
- (unsigned)tmp, len, phdr->p_vaddr, phdr->p_offset);
- goto fail;
- }
-
- /* If 'len' didn't end on page boundary, and it's a writable
- * segment, zero-fill the rest. */
- if (PAGE_OFFSET(len) > 0 && (phdr->p_flags & PF_W) != 0)
- memset((void *)(pbase + len), 0, PAGE_SIZE - PAGE_OFFSET(len));
-
- /* Check to see if we need to extend the map for this segment to
- * cover the diff between filesz and memsz (i.e. for bss).
- *
- * base _+---------------------+ page boundary
- * . .
- * | |
- * . .
- * pbase _+---------------------+ page boundary
- * | |
- * . .
- * base + p_vaddr _| |
- * . \ \ .
- * . | filesz | .
- * pbase + len _| / | |
- * <0 pad> . . .
- * extra_base _+------------|--------+ page boundary
- * / . . .
- * | . . .
- * | +------------|--------+ page boundary
- * extra_len-> | | | |
- * | . | memsz .
- * | . | .
- * \ _| / |
- * . .
- * | |
- * _+---------------------+ page boundary
- */
- tmp = (Elf32_Addr)PAGE_END((unsigned)pbase + len);
- if (tmp < (base + phdr->p_vaddr + phdr->p_memsz)) {
- extra_len = base + phdr->p_vaddr + phdr->p_memsz - tmp;
- TRACE("[ %5d - Need to extend segment from '%s' @ 0x%08x "
- "(0x%08x) ]\n", pid, si->name, (unsigned)tmp, extra_len);
- /* map in the extra page(s) as anonymous into the range.
- * This is probably not necessary as we already mapped in
- * the entire region previously, but we just want to be
- * sure. This will also set the right flags on the region
- * (though we can probably accomplish the same thing with
- * mprotect).
- */
- extra_base = mmap((void *)tmp, extra_len,
- PFLAGS_TO_PROT(phdr->p_flags),
- MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS,
- -1, 0);
- if (extra_base == MAP_FAILED) {
- DL_ERR("[ %5d - failed to extend segment from '%s' @ 0x%08x"
- " (0x%08x) ]", pid, si->name, (unsigned)tmp,
- extra_len);
- goto fail;
- }
- /* TODO: Check if we need to memset-0 this region.
- * Anonymous mappings are zero-filled copy-on-writes, so we
- * shouldn't need to. */
- TRACE("[ %5d - Segment from '%s' extended @ 0x%08x "
- "(0x%08x)\n", pid, si->name, (unsigned)extra_base,
- extra_len);
- }
- /* set the len here to show the full extent of the segment we
- * just loaded, mostly for debugging */
- len = PAGE_END((unsigned)base + phdr->p_vaddr + phdr->p_memsz) - (unsigned)pbase;
- TRACE("[ %5d - Successfully loaded segment from '%s' @ 0x%08x "
- "(0x%08x). p_vaddr=0x%08x p_offset=0x%08x\n", pid, si->name,
- (unsigned)pbase, len, phdr->p_vaddr, phdr->p_offset);
- total_sz += len;
- /* Make the section writable just in case we'll have to write to
- * it during relocation (i.e. text segment). However, we will
- * remember what range of addresses should be write protected.
- *
- */
- if (!(phdr->p_flags & PF_W)) {
- if ((unsigned)pbase < si->wrprotect_start)
- si->wrprotect_start = (unsigned)pbase;
- if (((unsigned)pbase + len) > si->wrprotect_end)
- si->wrprotect_end = (unsigned)pbase + len;
- mprotect(pbase, len,
- PFLAGS_TO_PROT(phdr->p_flags) | PROT_WRITE);
- }
- } else if (phdr->p_type == PT_GNU_RELRO) {
- if (((base + phdr->p_vaddr) >= si->base + si->size)
- || ((base + phdr->p_vaddr + phdr->p_memsz) > si->base + si->size)
- || ((base + phdr->p_vaddr + phdr->p_memsz) < si->base)) {
- DL_ERR("%d invalid GNU_RELRO in '%s' "
- "p_vaddr=0x%08x p_memsz=0x%08x", pid, si->name,
- phdr->p_vaddr, phdr->p_memsz);
- goto fail;
- }
- si->gnu_relro_start = (Elf32_Addr) (base + phdr->p_vaddr);
- si->gnu_relro_len = (unsigned) phdr->p_memsz;
- }
-
- }
-
- /* Sanity check */
- if (total_sz > si->size) {
- DL_ERR("%5d - Total length (0x%08x) of mapped segments from '%s' is "
- "greater than what was allocated (0x%08x). THIS IS BAD!",
- pid, total_sz, si->name, si->size);
- goto fail;
- }
-
- /* vaddr : Real virtual address in process' address space.
- * p_vaddr : Relative virtual address in ELF object
- * p_offset : File offset in ELF object
- *
- * vaddr p_vaddr p_offset
- * ----- ------------ --------
- * base 0
- * si->base PAGE_START(phdr0->p_vaddr)
- * phdr0->p_vaddr phdr0->p_offset
- * phdr ehdr->e_phoff
- */
- si->phdr = (Elf32_Phdr *)(base + phdr0->p_vaddr +
- ehdr_phoff - phdr0->p_offset);
- si->phnum = phdr_count;
-
- TRACE("[ %5d - Finish loading segments for '%s' @ 0x%08x. "
- "Total memory footprint: 0x%08x bytes ]\n", pid, si->name,
- (unsigned)si->base, si->size);
- return 0;
-
-fail:
- /* We can just blindly unmap the entire region even though some things
- * were mapped in originally with anonymous and others could have been
- * been mapped in from the file before we failed. The kernel will unmap
- * all the pages in the range, irrespective of how they got there.
- */
- munmap((void *)si->base, si->size);
- si->flags |= FLAG_ERROR;
- return -1;
-}
-
-/* TODO: Implement this to take care of the fact that Android ARM
- * ELF objects shove everything into a single loadable segment that has the
- * write bit set. wr_offset is then used to set non-(data|bss) pages to be
- * non-writable.
- */
-#if 0
-static unsigned
-get_wr_offset(int fd, const char *name, Elf32_Ehdr *ehdr)
-{
- Elf32_Shdr *shdr_start;
- Elf32_Shdr *shdr;
- int shdr_sz = ehdr->e_shnum * sizeof(Elf32_Shdr);
- int cnt;
- unsigned wr_offset = 0xffffffff;
-
- shdr_start = mmap(0, shdr_sz, PROT_READ, MAP_PRIVATE, fd,
- PAGE_START(ehdr->e_shoff));
- if (shdr_start == MAP_FAILED) {
- WARN("%5d - Could not read section header info from '%s'. Will not "
- "not be able to determine write-protect offset.\n", pid, name);
- return (unsigned)-1;
- }
-
- for(cnt = 0, shdr = shdr_start; cnt < ehdr->e_shnum; ++cnt, ++shdr) {
- if ((shdr->sh_type != SHT_NULL) && (shdr->sh_flags & SHF_WRITE) &&
- (shdr->sh_addr < wr_offset)) {
- wr_offset = shdr->sh_addr;
- }
- }
-
- munmap(shdr_start, shdr_sz);
- return wr_offset;
-}
-#endif
-
-
static soinfo *
load_library(const char *name)
{
@@ -1026,6 +713,10 @@
Elf32_Addr phdr_size;
const Elf32_Phdr* phdr_table;
+ void* load_start = NULL;
+ Elf32_Addr load_size = 0;
+ Elf32_Addr load_bias = 0;
+
if (fd == -1) {
DL_ERR("Library '%s' not found", name);
return NULL;
@@ -1089,21 +780,60 @@
if (si == NULL)
goto fail;
- /* Carve out a chunk of memory where we will map in the individual
- * segments */
- si->base = req_base;
- si->size = ext_sz;
+ /* Reserve address space for all loadable segments */
+ ret = phdr_table_reserve_memory(phdr_table,
+ phdr_count,
+ req_base,
+ &load_start,
+ &load_size,
+ &load_bias);
+ if (ret < 0) {
+ DL_ERR("%5d Can't reserve %d bytes from 0x%08x in address space for %s: %s",
+ pid, ext_sz, req_base, name, strerror(errno));
+ goto fail;
+ }
+
+ TRACE("[ %5d allocated memory for %s @ %p (0x%08x) ]\n",
+ pid, name, load_start, load_size);
+
+ /* Map all the segments in our address space with default protections */
+ ret = phdr_table_load_segments(phdr_table,
+ phdr_count,
+ load_start,
+ load_size,
+ load_bias,
+ fd);
+ if (ret < 0) {
+ DL_ERR("%5d Can't map loadable segments for %s: %s",
+ pid, name, strerror(errno));
+ goto fail;
+ }
+
+ /* Unprotect the segments, i.e. make them writable, to allow
+ * relocations to work properly. We will later call
+ * phdr_table_protect_segments() after all of them are applied
+ * and all constructors are run.
+ */
+ ret = phdr_table_unprotect_segments(phdr_table,
+ phdr_count,
+ load_bias);
+ if (ret < 0) {
+ DL_ERR("%5d Can't unprotect loadable segments for %s: %s",
+ pid, name, strerror(errno));
+ goto fail;
+ }
+
+ si->base = (Elf32_Addr) load_start;
+ si->size = load_size;
+ si->load_bias = load_bias;
si->flags = 0;
si->entry = 0;
si->dynamic = (unsigned *)-1;
- if (soinfo_alloc_mem_region(si) < 0)
- goto fail;
-
- TRACE("[ %5d allocated memory for %s @ %p (0x%08x) ]\n",
- pid, name, (void *)si->base, (unsigned) ext_sz);
-
- /* Now actually load the library's segments into right places in memory */
- if (soinfo_load_segments(si, fd, phdr_table, phdr_count, header->e_phoff) < 0) {
+ si->phnum = phdr_count;
+ si->phdr = phdr_table_get_loaded_phdr(phdr_table, phdr_count, load_bias);
+ if (si->phdr == NULL) {
+ DL_ERR("%5d Can't find loaded PHDR for %s",
+ pid, name);
goto fail;
}
@@ -1192,14 +922,11 @@
* Make sure that we undo the PT_GNU_RELRO protections we added
* in soinfo_link_image. This is needed to undo the DT_NEEDED hack below.
*/
- if ((si->gnu_relro_start != 0) && (si->gnu_relro_len != 0)) {
- Elf32_Addr start = PAGE_START(si->gnu_relro_start);
- unsigned len = (si->gnu_relro_start - start) + si->gnu_relro_len;
- if (mprotect((void *) start, len, PROT_READ | PROT_WRITE) < 0)
- DL_ERR("%5d %s: could not undo GNU_RELRO protections. "
- "Expect a crash soon. errno=%d (%s)",
- pid, si->name, errno, strerror(errno));
-
+ if (phdr_table_unprotect_gnu_relro(si->phdr, si->phnum,
+ si->load_bias) < 0) {
+ DL_ERR("%5d %s: could not undo GNU_RELRO protections. "
+ "Expect a crash soon. errno=%d (%s)",
+ pid, si->name, errno, strerror(errno));
}
for(d = si->dynamic; *d; d += 2) {
@@ -1634,20 +1361,28 @@
unsigned *d;
/* "base" might wrap around UINT32_MAX. */
Elf32_Addr base = si->load_bias;
- Elf32_Phdr *phdr = si->phdr;
+ const Elf32_Phdr *phdr = si->phdr;
int phnum = si->phnum;
+ int relocating_linker = (si->flags & FLAG_LINKER) != 0;
- INFO("[ %5d linking %s ]\n", pid, si->name);
- DEBUG("%5d si->base = 0x%08x si->flags = 0x%08x\n", pid,
- si->base, si->flags);
+ /* We can't debug anything until the linker is relocated */
+ if (!relocating_linker) {
+ INFO("[ %5d linking %s ]\n", pid, si->name);
+ DEBUG("%5d si->base = 0x%08x si->flags = 0x%08x\n", pid,
+ si->base, si->flags);
+ }
/* Extract dynamic section */
si->dynamic = phdr_table_get_dynamic_section(phdr, phnum, base);
if (si->dynamic == NULL) {
- DL_ERR("%5d missing PT_DYNAMIC?!", pid);
+ if (!relocating_linker) {
+ DL_ERR("%5d missing PT_DYNAMIC?!", pid);
+ }
goto fail;
} else {
- DEBUG("%5d dynamic = %p\n", pid, si->dynamic);
+ if (!relocating_linker) {
+ DEBUG("%5d dynamic = %p\n", pid, si->dynamic);
+ }
}
#ifdef ANDROID_ARM_LINKER
@@ -1656,65 +1391,16 @@
#endif
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.
- * If this was a dynamic lib, that would have been done at load time.
- *
- * TODO: It's unfortunate that small pieces of this are
- * repeated from the load_library routine. Refactor this just
- * slightly to reuse these bits.
- */
- si->size = 0;
- for(; phnum > 0; --phnum, ++phdr) {
- if (phdr->p_type == PT_LOAD) {
- /* For the executable, we use the si->size field only in
- dl_unwind_find_exidx(), so the meaning of si->size
- is not the size of the executable; it is the distance
- between the load location of the executable and the last
- address of the loadable part of the executable.
- We use the range [si->base, si->base + si->size) to
- determine whether a PC value falls within the executable
- section. Of course, if a value is between si->base and
- (base + phdr->p_vaddr), it's not in the executable
- section, but a) we shouldn't be asking for such a value
- anyway, and b) if we have to provide an EXIDX for such a
- value, then the executable's EXIDX is probably the better
- choice.
- */
- DEBUG_DUMP_PHDR(phdr, "PT_LOAD", pid);
- if (phdr->p_vaddr + phdr->p_memsz > si->size)
- si->size = phdr->p_vaddr + phdr->p_memsz;
- /* try to remember what range of addresses should be write
- * protected */
- if (!(phdr->p_flags & PF_W)) {
- unsigned _end;
-
- if (base + phdr->p_vaddr < si->wrprotect_start)
- si->wrprotect_start = base + phdr->p_vaddr;
- _end = PAGE_END(base + phdr->p_vaddr + phdr->p_memsz);
- if (_end > si->wrprotect_end)
- si->wrprotect_end = _end;
- /* Make the section writable just in case we'll have to
- * write to it during relocation (i.e. text segment).
- * However, we will remember what range of addresses
- * should be write protected.
- */
- mprotect((void *) (base + phdr->p_vaddr),
- phdr->p_memsz,
- PFLAGS_TO_PROT(phdr->p_flags) | PROT_WRITE);
- }
- } else if (phdr->p_type == PT_GNU_RELRO) {
- if ((base + phdr->p_vaddr >= si->base + si->size)
- || ((base + phdr->p_vaddr + phdr->p_memsz) > si->base + si->size)
- || ((base + phdr->p_vaddr + phdr->p_memsz) < si->base)) {
- DL_ERR("%d invalid GNU_RELRO in '%s' "
- "p_vaddr=0x%08x p_memsz=0x%08x", pid, si->name,
- phdr->p_vaddr, phdr->p_memsz);
- goto fail;
- }
- si->gnu_relro_start = (Elf32_Addr) (base + phdr->p_vaddr);
- si->gnu_relro_len = (unsigned) phdr->p_memsz;
+ if (phdr_table_unprotect_segments(si->phdr,
+ si->phnum,
+ si->load_bias) < 0) {
+ /* We can't call DL_ERR if the linker's relocations haven't
+ * been performed yet */
+ if (!relocating_linker) {
+ DL_ERR("%5d Can't unprotect segments for %s: %s",
+ pid, si->name, strerror(errno));
}
+ goto fail;
}
}
@@ -1870,40 +1556,19 @@
si->flags |= FLAG_LINKED;
DEBUG("[ %5d finished linking %s ]\n", pid, si->name);
-#if 0
- /* This is the way that the old dynamic linker did protection of
- * non-writable areas. It would scan section headers and find where
- * .text ended (rather where .data/.bss began) and assume that this is
- * the upper range of the non-writable area. This is too coarse,
- * and is kept here for reference until we fully move away from single
- * segment elf objects. See the code in get_wr_offset (also #if'd 0)
- * that made this possible.
- */
- if(wr_offset < 0xffffffff){
- mprotect((void*) si->base, wr_offset, PROT_READ | PROT_EXEC);
+ /* All relocations are done, we can protect our segments back to
+ * read-only. */
+ if (phdr_table_protect_segments(si->phdr, si->phnum, si->load_bias) < 0) {
+ DL_ERR("%5d Can't protect segments for %s: %s",
+ pid, si->name, strerror(errno));
+ goto fail;
}
-#else
- /* TODO: Verify that this does the right thing in all cases, as it
- * presently probably does not. It is possible that an ELF image will
- * come with multiple read-only segments. What we ought to do is scan
- * the program headers again and mprotect all the read-only segments.
- * To prevent re-scanning the program header, we would have to build a
- * list of loadable segments in si, and then scan that instead. */
- if (si->wrprotect_start != 0xffffffff && si->wrprotect_end != 0) {
- mprotect((void *)si->wrprotect_start,
- si->wrprotect_end - si->wrprotect_start,
- PROT_READ | PROT_EXEC);
- }
-#endif
- if (si->gnu_relro_start != 0 && si->gnu_relro_len != 0) {
- Elf32_Addr start = PAGE_START(si->gnu_relro_start);
- unsigned len = (si->gnu_relro_start - start) + si->gnu_relro_len;
- if (mprotect((void *) start, len, PROT_READ) < 0) {
- DL_ERR("%5d GNU_RELRO mprotect of library '%s' failed: %d (%s)\n",
- pid, si->name, errno, strerror(errno));
- goto fail;
- }
+ /* We can also turn on GNU RELRO protection */
+ if (phdr_table_protect_gnu_relro(si->phdr, si->phnum, si->load_bias) < 0) {
+ DL_ERR("%5d Can't enable GNU RELRO protection for %s: %s",
+ pid, si->name, strerror(errno));
+ goto fail;
}
/* If this is a SET?ID program, dup /dev/null to opened stdin,
@@ -2098,6 +1763,7 @@
*/
int nn;
si->base = 0;
+ si->size = phdr_table_get_load_size(si->phdr, si->phnum);
si->load_bias = 0;
for ( nn = 0; nn < si->phnum; nn++ ) {
if (si->phdr[nn].p_type == PT_PHDR) {
@@ -2107,11 +1773,7 @@
}
}
si->dynamic = (unsigned *)-1;
- si->wrprotect_start = 0xffffffff;
- si->wrprotect_end = 0;
si->refcount = 1;
- si->gnu_relro_start = 0;
- si->gnu_relro_len = 0;
/* Use LD_LIBRARY_PATH if we aren't setuid/setgid */
if (ldpath_env)
@@ -2249,15 +1911,12 @@
memset(&linker_so, 0, sizeof(soinfo));
linker_so.base = linker_addr;
+ linker_so.size = phdr_table_get_load_size(phdr, elf_hdr->e_phnum);
linker_so.load_bias = get_elf_exec_load_bias(elf_hdr);
linker_so.dynamic = (unsigned *) -1;
linker_so.phdr = phdr;
linker_so.phnum = elf_hdr->e_phnum;
linker_so.flags |= FLAG_LINKER;
- linker_so.wrprotect_start = 0xffffffff;
- linker_so.wrprotect_end = 0;
- linker_so.gnu_relro_start = 0;
- linker_so.gnu_relro_len = 0;
if (soinfo_link_image(&linker_so, 0)) {
// It would be nice to print an error message, but if the linker
diff --git a/linker/linker.h b/linker/linker.h
index e95feb2..0956ac5 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -107,7 +107,7 @@
struct soinfo
{
const char name[SOINFO_NAME_LEN];
- Elf32_Phdr *phdr;
+ const Elf32_Phdr *phdr;
int phnum;
unsigned entry;
unsigned base;
@@ -117,8 +117,8 @@
unsigned *dynamic;
- unsigned wrprotect_start;
- unsigned wrprotect_end;
+ unsigned unused2; // DO NOT USE, maintained for compatibility
+ unsigned unused3; // DO NOT USE, maintained for compatibility
soinfo *next;
unsigned flags;
@@ -161,9 +161,6 @@
int constructors_called;
- Elf32_Addr gnu_relro_start;
- unsigned gnu_relro_len;
-
/* When you read a virtual address from the ELF file, add this
* value to get the corresponding address in the process' address space */
Elf32_Addr load_bias;
