merge in jb-mr2-release history after reset to jb-mr2-dev
diff --git a/libc/Android.mk b/libc/Android.mk
index f146759..21d3089 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -111,35 +111,8 @@
string/strspn.c \
string/strstr.c \
string/strtok.c \
- wchar/wcpcpy.c \
- wchar/wcpncpy.c \
- wchar/wcscasecmp.c \
- wchar/wcscat.c \
- wchar/wcschr.c \
- wchar/wcscmp.c \
- wchar/wcscpy.c \
- wchar/wcscspn.c \
- wchar/wcsdup.c \
- wchar/wcslcat.c \
- wchar/wcslcpy.c \
- wchar/wcslen.c \
- wchar/wcsncasecmp.c \
- wchar/wcsncat.c \
- wchar/wcsncmp.c \
- wchar/wcsncpy.c \
- wchar/wcsnlen.c \
- wchar/wcspbrk.c \
- wchar/wcsrchr.c \
- wchar/wcsspn.c \
- wchar/wcsstr.c \
- wchar/wcstok.c \
wchar/wcswidth.c \
wchar/wcsxfrm.c \
- wchar/wmemchr.c \
- wchar/wmemcmp.c \
- wchar/wmemcpy.c \
- wchar/wmemmove.c \
- wchar/wmemset.c \
tzcode/asctime.c \
tzcode/difftime.c \
tzcode/localtime.c \
@@ -318,6 +291,33 @@
libc_upstream_freebsd_src_files := \
upstream-freebsd/lib/libc/stdlib/realpath.c \
+ upstream-freebsd/lib/libc/string/wcpcpy.c \
+ upstream-freebsd/lib/libc/string/wcpncpy.c \
+ upstream-freebsd/lib/libc/string/wcscasecmp.c \
+ upstream-freebsd/lib/libc/string/wcscat.c \
+ upstream-freebsd/lib/libc/string/wcschr.c \
+ upstream-freebsd/lib/libc/string/wcscmp.c \
+ upstream-freebsd/lib/libc/string/wcscpy.c \
+ upstream-freebsd/lib/libc/string/wcscspn.c \
+ upstream-freebsd/lib/libc/string/wcsdup.c \
+ upstream-freebsd/lib/libc/string/wcslcat.c \
+ upstream-freebsd/lib/libc/string/wcslcpy.c \
+ upstream-freebsd/lib/libc/string/wcslen.c \
+ upstream-freebsd/lib/libc/string/wcsncasecmp.c \
+ upstream-freebsd/lib/libc/string/wcsncat.c \
+ upstream-freebsd/lib/libc/string/wcsncmp.c \
+ upstream-freebsd/lib/libc/string/wcsncpy.c \
+ upstream-freebsd/lib/libc/string/wcsnlen.c \
+ upstream-freebsd/lib/libc/string/wcspbrk.c \
+ upstream-freebsd/lib/libc/string/wcsrchr.c \
+ upstream-freebsd/lib/libc/string/wcsspn.c \
+ upstream-freebsd/lib/libc/string/wcsstr.c \
+ upstream-freebsd/lib/libc/string/wcstok.c \
+ upstream-freebsd/lib/libc/string/wmemchr.c \
+ upstream-freebsd/lib/libc/string/wmemcmp.c \
+ upstream-freebsd/lib/libc/string/wmemcpy.c \
+ upstream-freebsd/lib/libc/string/wmemmove.c \
+ upstream-freebsd/lib/libc/string/wmemset.c \
libc_upstream_netbsd_src_files := \
upstream-netbsd/common/lib/libc/hash/sha1/sha1.c \
diff --git a/libc/arch-arm/bionic/memcpy.a15.S b/libc/arch-arm/bionic/memcpy.a15.S
index d1bfb7c..516e20c 100644
--- a/libc/arch-arm/bionic/memcpy.a15.S
+++ b/libc/arch-arm/bionic/memcpy.a15.S
@@ -26,12 +26,6 @@
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
-#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED) || \
- (!(defined (__ARM_ARCH_7A__))))
-
- /* Do nothing here. See memcpy-stub.c in the same directory. */
-
-#else
/* Prototype: void *memcpy (void *dst, const void *src, size_t count). */
/* Use the version of memcpy implemented using LDRD and STRD.
@@ -50,16 +44,12 @@
destination register must be even and the second consecutive in
ARM state, but not in Thumb state. */
+#include <machine/cpu-features.h>
+#include <machine/asm.h>
+
.syntax unified
-#if defined (__thumb__)
- .thumb
- .thumb_func
-#endif
-
- .global memcpy
- .type memcpy, %function
-memcpy:
+ENTRY(memcpy)
/* Assumes that n >= 0, and dst, src are valid pointers.
If there is at least 8 bytes to copy, use LDRD/STRD.
@@ -69,12 +59,16 @@
When less than 8 left, copy a word and then byte by byte. */
/* Save registers (r0 holds the return value):
- optimized push {r0, r4, r5, lr}.
+ optimized push {r0, r4, r5, r6, r7, lr}.
To try and improve performance, stack layout changed,
i.e., not keeping the stack looking like users expect
(highest numbered register at highest address). */
- push {r0, lr}
- strd r4, r5, [sp, #-8]!
+ .save {r0, lr}
+ push {r0, lr}
+ .save {r4, r5}
+ strd r4, r5, [sp, #-8]!
+ .save {r6, r7}
+ strd r6, r7, [sp, #-8]!
/* TODO: Add debug frame directives.
We don't need exception unwind directives, because the code below
@@ -194,9 +188,11 @@
strbcs r5, [r0]
return:
- /* Restore registers: optimized pop {r0, r4, r5, pc} */
+ /* Restore registers: optimized pop {r0, r4, r5, r6, r7, pc} */
+ /* This is the only return point of memcpy. */
+ ldrd r6, r7, [sp], #8
ldrd r4, r5, [sp], #8
- pop {r0, pc} /* This is the only return point of memcpy. */
+ pop {r0, pc}
#ifndef __ARM_FEATURE_UNALIGNED
@@ -223,12 +219,6 @@
/* Get here if there is more than 8 bytes to copy.
The number of bytes to copy is r2+8, r2 >= 0. */
- /* Save registers: push { r6, r7 }.
- We need additional registers for LDRD and STRD, because in ARM state
- the first destination register must be even and the second
- consecutive. */
- strd r6, r7, [sp, #-8]!
-
subs r2, r2, #56
blt 4f /* Go to misaligned copy of less than 64 bytes. */
@@ -259,10 +249,6 @@
/* Restore the count if there is more than 7 bytes to copy. */
adds r2, r2, #56
- /* If less than 8 bytes to copy,
- restore registers saved for this loop: optimized poplt { r6, r7 }. */
- itt lt
- ldrdlt r6, r7, [sp], #8
blt 6f /* Go to misaligned copy of less than 8 bytes. */
5:
@@ -278,9 +264,6 @@
subs r2, r2, #8
bge 5b /* If there is more to copy. */
- /* Restore registers saved for this loop: optimized pop { r6, r7 }. */
- ldrd r6, r7, [sp], #8
-
6:
/* Get here if there less than 8 bytes to copy (-8 <= r2 < 0)
and they are misaligned. */
@@ -420,4 +403,4 @@
#endif /* not __ARM_FEATURE_UNALIGNED */
-#endif /* memcpy */
+END(memcpy)
diff --git a/libc/include/wchar.h b/libc/include/wchar.h
index ef88e04..a4e19f0 100644
--- a/libc/include/wchar.h
+++ b/libc/include/wchar.h
@@ -149,6 +149,11 @@
extern wint_t towctrans(wint_t, wctrans_t);
extern wctrans_t wctrans (const char *);
+#if _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L
+wchar_t* wcsdup(const wchar_t*);
+size_t wcsnlen(const wchar_t*, size_t);
+#endif
+
__END_DECLS
#endif /* _WCHAR_H_ */
diff --git a/libc/wchar/wcpcpy.c b/libc/upstream-freebsd/lib/libc/string/wcpcpy.c
similarity index 100%
rename from libc/wchar/wcpcpy.c
rename to libc/upstream-freebsd/lib/libc/string/wcpcpy.c
diff --git a/libc/wchar/wcpncpy.c b/libc/upstream-freebsd/lib/libc/string/wcpncpy.c
similarity index 100%
rename from libc/wchar/wcpncpy.c
rename to libc/upstream-freebsd/lib/libc/string/wcpncpy.c
diff --git a/libc/wchar/wcscasecmp.c b/libc/upstream-freebsd/lib/libc/string/wcscasecmp.c
similarity index 100%
rename from libc/wchar/wcscasecmp.c
rename to libc/upstream-freebsd/lib/libc/string/wcscasecmp.c
diff --git a/libc/wchar/wcscat.c b/libc/upstream-freebsd/lib/libc/string/wcscat.c
similarity index 100%
rename from libc/wchar/wcscat.c
rename to libc/upstream-freebsd/lib/libc/string/wcscat.c
diff --git a/libc/wchar/wcschr.c b/libc/upstream-freebsd/lib/libc/string/wcschr.c
similarity index 100%
rename from libc/wchar/wcschr.c
rename to libc/upstream-freebsd/lib/libc/string/wcschr.c
diff --git a/libc/wchar/wcscmp.c b/libc/upstream-freebsd/lib/libc/string/wcscmp.c
similarity index 100%
rename from libc/wchar/wcscmp.c
rename to libc/upstream-freebsd/lib/libc/string/wcscmp.c
diff --git a/libc/wchar/wcscpy.c b/libc/upstream-freebsd/lib/libc/string/wcscpy.c
similarity index 100%
rename from libc/wchar/wcscpy.c
rename to libc/upstream-freebsd/lib/libc/string/wcscpy.c
diff --git a/libc/wchar/wcscspn.c b/libc/upstream-freebsd/lib/libc/string/wcscspn.c
similarity index 100%
rename from libc/wchar/wcscspn.c
rename to libc/upstream-freebsd/lib/libc/string/wcscspn.c
diff --git a/libc/wchar/wcsdup.c b/libc/upstream-freebsd/lib/libc/string/wcsdup.c
similarity index 100%
rename from libc/wchar/wcsdup.c
rename to libc/upstream-freebsd/lib/libc/string/wcsdup.c
diff --git a/libc/wchar/wcslcat.c b/libc/upstream-freebsd/lib/libc/string/wcslcat.c
similarity index 100%
rename from libc/wchar/wcslcat.c
rename to libc/upstream-freebsd/lib/libc/string/wcslcat.c
diff --git a/libc/wchar/wcslcpy.c b/libc/upstream-freebsd/lib/libc/string/wcslcpy.c
similarity index 100%
rename from libc/wchar/wcslcpy.c
rename to libc/upstream-freebsd/lib/libc/string/wcslcpy.c
diff --git a/libc/wchar/wcslen.c b/libc/upstream-freebsd/lib/libc/string/wcslen.c
similarity index 100%
rename from libc/wchar/wcslen.c
rename to libc/upstream-freebsd/lib/libc/string/wcslen.c
diff --git a/libc/wchar/wcsncasecmp.c b/libc/upstream-freebsd/lib/libc/string/wcsncasecmp.c
similarity index 100%
rename from libc/wchar/wcsncasecmp.c
rename to libc/upstream-freebsd/lib/libc/string/wcsncasecmp.c
diff --git a/libc/wchar/wcsncat.c b/libc/upstream-freebsd/lib/libc/string/wcsncat.c
similarity index 100%
rename from libc/wchar/wcsncat.c
rename to libc/upstream-freebsd/lib/libc/string/wcsncat.c
diff --git a/libc/wchar/wcsncmp.c b/libc/upstream-freebsd/lib/libc/string/wcsncmp.c
similarity index 100%
rename from libc/wchar/wcsncmp.c
rename to libc/upstream-freebsd/lib/libc/string/wcsncmp.c
diff --git a/libc/wchar/wcsncpy.c b/libc/upstream-freebsd/lib/libc/string/wcsncpy.c
similarity index 100%
rename from libc/wchar/wcsncpy.c
rename to libc/upstream-freebsd/lib/libc/string/wcsncpy.c
diff --git a/libc/wchar/wcsnlen.c b/libc/upstream-freebsd/lib/libc/string/wcsnlen.c
similarity index 100%
rename from libc/wchar/wcsnlen.c
rename to libc/upstream-freebsd/lib/libc/string/wcsnlen.c
diff --git a/libc/wchar/wcspbrk.c b/libc/upstream-freebsd/lib/libc/string/wcspbrk.c
similarity index 100%
rename from libc/wchar/wcspbrk.c
rename to libc/upstream-freebsd/lib/libc/string/wcspbrk.c
diff --git a/libc/wchar/wcsrchr.c b/libc/upstream-freebsd/lib/libc/string/wcsrchr.c
similarity index 100%
rename from libc/wchar/wcsrchr.c
rename to libc/upstream-freebsd/lib/libc/string/wcsrchr.c
diff --git a/libc/wchar/wcsspn.c b/libc/upstream-freebsd/lib/libc/string/wcsspn.c
similarity index 100%
rename from libc/wchar/wcsspn.c
rename to libc/upstream-freebsd/lib/libc/string/wcsspn.c
diff --git a/libc/wchar/wcsstr.c b/libc/upstream-freebsd/lib/libc/string/wcsstr.c
similarity index 100%
rename from libc/wchar/wcsstr.c
rename to libc/upstream-freebsd/lib/libc/string/wcsstr.c
diff --git a/libc/wchar/wcstok.c b/libc/upstream-freebsd/lib/libc/string/wcstok.c
similarity index 100%
rename from libc/wchar/wcstok.c
rename to libc/upstream-freebsd/lib/libc/string/wcstok.c
diff --git a/libc/wchar/wmemchr.c b/libc/upstream-freebsd/lib/libc/string/wmemchr.c
similarity index 100%
rename from libc/wchar/wmemchr.c
rename to libc/upstream-freebsd/lib/libc/string/wmemchr.c
diff --git a/libc/wchar/wmemcmp.c b/libc/upstream-freebsd/lib/libc/string/wmemcmp.c
similarity index 100%
rename from libc/wchar/wmemcmp.c
rename to libc/upstream-freebsd/lib/libc/string/wmemcmp.c
diff --git a/libc/wchar/wmemcpy.c b/libc/upstream-freebsd/lib/libc/string/wmemcpy.c
similarity index 100%
rename from libc/wchar/wmemcpy.c
rename to libc/upstream-freebsd/lib/libc/string/wmemcpy.c
diff --git a/libc/wchar/wmemmove.c b/libc/upstream-freebsd/lib/libc/string/wmemmove.c
similarity index 100%
rename from libc/wchar/wmemmove.c
rename to libc/upstream-freebsd/lib/libc/string/wmemmove.c
diff --git a/libc/wchar/wmemset.c b/libc/upstream-freebsd/lib/libc/string/wmemset.c
similarity index 100%
rename from libc/wchar/wmemset.c
rename to libc/upstream-freebsd/lib/libc/string/wmemset.c
diff --git a/libc/zoneinfo/tzdata b/libc/zoneinfo/tzdata
index 019650e..bd59e05 100644
--- a/libc/zoneinfo/tzdata
+++ b/libc/zoneinfo/tzdata
Binary files differ
diff --git a/linker/debugger.cpp b/linker/debugger.cpp
index 492ca4b..586cd2f 100644
--- a/linker/debugger.cpp
+++ b/linker/debugger.cpp
@@ -174,7 +174,7 @@
* Catches fatal signals so we can ask debuggerd to ptrace us before
* we crash.
*/
-void debugger_signal_handler(int n, siginfo_t* info, void*) {
+void debuggerd_signal_handler(int n, siginfo_t* info, void*) {
/*
* It's possible somebody cleared the SA_SIGINFO flag, which would mean
* our "info" arg holds an undefined value.
@@ -245,10 +245,10 @@
}
}
-void debugger_init() {
+void debuggerd_init() {
struct sigaction act;
memset(&act, 0, sizeof(act));
- act.sa_sigaction = debugger_signal_handler;
+ act.sa_sigaction = debuggerd_signal_handler;
act.sa_flags = SA_RESTART | SA_SIGINFO;
sigemptyset(&act.sa_mask);
diff --git a/linker/dlfcn.cpp b/linker/dlfcn.cpp
index a5f8944..0b38ec4 100644
--- a/linker/dlfcn.cpp
+++ b/linker/dlfcn.cpp
@@ -64,7 +64,7 @@
ScopedPthreadMutexLocker locker(&gDlMutex);
soinfo* result = do_dlopen(filename, flags);
if (result == NULL) {
- __bionic_format_dlerror("dlopen failed", linker_get_error());
+ __bionic_format_dlerror("dlopen failed", linker_get_error_buffer());
return NULL;
}
return result;
@@ -85,18 +85,18 @@
soinfo* found = NULL;
Elf32_Sym* sym = NULL;
if (handle == RTLD_DEFAULT) {
- sym = lookup(symbol, &found, NULL);
+ sym = dlsym_linear_lookup(symbol, &found, NULL);
} else if (handle == RTLD_NEXT) {
void* ret_addr = __builtin_return_address(0);
soinfo* si = find_containing_library(ret_addr);
sym = NULL;
if (si && si->next) {
- sym = lookup(symbol, &found, si->next);
+ sym = dlsym_linear_lookup(symbol, &found, si->next);
}
} else {
- found = (soinfo*) handle;
- sym = soinfo_lookup(found, symbol);
+ found = reinterpret_cast<soinfo*>(handle);
+ sym = dlsym_handle_lookup(found, symbol);
}
if (sym != NULL) {
@@ -131,7 +131,7 @@
info->dli_fbase = (void*) si->base;
// Determine if any symbol in the library contains the specified address.
- Elf32_Sym *sym = soinfo_find_symbol(si, addr);
+ Elf32_Sym *sym = dladdr_find_symbol(si, addr);
if (sym != NULL) {
info->dli_sname = si->strtab + sym->st_name;
info->dli_saddr = (void*)(si->load_bias + sym->st_value);
diff --git a/linker/linker.cpp b/linker/linker.cpp
index d36b1f6..db0c9f1 100755
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -41,7 +41,6 @@
// Private C library headers.
#include <private/bionic_tls.h>
-#include <private/debug_format.h>
#include <private/KernelArgumentBlock.h>
#include <private/logd.h>
#include <private/ScopedPthreadMutexLocker.h>
@@ -87,9 +86,9 @@
static struct soinfo_pool_t* gSoInfoPools = NULL;
static soinfo* gSoInfoFreeList = NULL;
-static soinfo *solist = &libdl_info;
-static soinfo *sonext = &libdl_info;
-static soinfo *somain; /* main process, always the one after libdl_info */
+static soinfo* solist = &libdl_info;
+static soinfo* sonext = &libdl_info;
+static soinfo* somain; /* main process, always the one after libdl_info */
static const char* const gSoPaths[] = {
"/vendor/lib",
@@ -103,9 +102,9 @@
static char gLdPreloadsBuffer[LDPRELOAD_BUFSIZE];
static const char* gLdPreloadNames[LDPRELOAD_MAX + 1];
-static soinfo *preloads[LDPRELOAD_MAX + 1];
+static soinfo* gLdPreloads[LDPRELOAD_MAX + 1];
-static int debug_verbosity;
+__LIBC_HIDDEN__ int gLdDebugVerbosity;
enum RelocationKind {
kRelocAbsolute = 0,
@@ -158,17 +157,15 @@
static char tmp_err_buf[768];
static char __linker_dl_err_buf[768];
-#define DL_ERR(fmt, x...) \
- do { \
- __libc_format_buffer(__linker_dl_err_buf, sizeof(__linker_dl_err_buf), fmt, ##x); \
- /* If LD_DEBUG is set high enough, send every dlerror(3) message to the log. */ \
- DEBUG(fmt "\n", ##x); \
- } while(0)
-const char* linker_get_error() {
+char* linker_get_error_buffer() {
return &__linker_dl_err_buf[0];
}
+size_t linker_get_error_buffer_size() {
+ return sizeof(__linker_dl_err_buf);
+}
+
/*
* This function is an empty stub where GDB locates a breakpoint to get notified
* about linker activity.
@@ -332,13 +329,13 @@
TRACE("name %s: freeing soinfo @ %p\n", si->name, si);
- for(trav = solist; trav != NULL; trav = trav->next){
+ for (trav = solist; trav != NULL; trav = trav->next) {
if (trav == si)
break;
prev = trav;
}
if (trav == NULL) {
- /* si was not ni solist */
+ /* si was not in solist */
DL_ERR("name \"%s\" is not in solist!", si->name);
return;
}
@@ -347,7 +344,9 @@
always the static libdl_info.
*/
prev->next = si->next;
- if (si == sonext) sonext = prev;
+ if (si == sonext) {
+ sonext = prev;
+ }
si->next = gSoInfoFreeList;
gSoInfoFreeList = si;
}
@@ -440,27 +439,27 @@
#endif
-static Elf32_Sym *soinfo_elf_lookup(soinfo *si, unsigned hash, const char *name)
-{
- Elf32_Sym *s;
- Elf32_Sym *symtab = si->symtab;
- const char *strtab = si->strtab;
+static Elf32_Sym* soinfo_elf_lookup(soinfo* si, unsigned hash, const char* name) {
+ Elf32_Sym* s;
+ Elf32_Sym* symtab = si->symtab;
+ const char* strtab = si->strtab;
unsigned n;
TRACE_TYPE(LOOKUP, "SEARCH %s in %s@0x%08x %08x %d\n",
name, si->name, si->base, hash, hash % si->nbucket);
n = hash % si->nbucket;
- for(n = si->bucket[hash % si->nbucket]; n != 0; n = si->chain[n]){
+ for (n = si->bucket[hash % si->nbucket]; n != 0; n = si->chain[n]) {
s = symtab + n;
- if(strcmp(strtab + s->st_name, name)) continue;
+ if (strcmp(strtab + s->st_name, name)) continue;
/* only concern ourselves with global and weak symbol definitions */
switch(ELF32_ST_BIND(s->st_info)){
case STB_GLOBAL:
case STB_WEAK:
- if(s->st_shndx == SHN_UNDEF)
+ if (s->st_shndx == SHN_UNDEF) {
continue;
+ }
TRACE_TYPE(LOOKUP, "FOUND %s in %s (%08x) %d\n",
name, si->name, s->st_value, s->st_size);
@@ -471,9 +470,8 @@
return NULL;
}
-static unsigned elfhash(const char *_name)
-{
- const unsigned char *name = (const unsigned char *) _name;
+static unsigned elfhash(const char* _name) {
+ const unsigned char* name = (const unsigned char*) _name;
unsigned h = 0, g;
while(*name) {
@@ -485,13 +483,9 @@
return h;
}
-static Elf32_Sym *
-soinfo_do_lookup(soinfo *si, const char *name, soinfo **lsi,
- soinfo *needed[])
-{
+static Elf32_Sym* soinfo_do_lookup(soinfo* si, const char* name, soinfo** lsi, soinfo* needed[]) {
unsigned elf_hash = elfhash(name);
- Elf32_Sym *s = NULL;
- int i;
+ Elf32_Sym* s = NULL;
if (si != NULL && somain != NULL) {
@@ -559,15 +553,15 @@
}
/* Next, look for it in the preloads list */
- for(i = 0; preloads[i] != NULL; i++) {
- s = soinfo_elf_lookup(preloads[i], elf_hash, name);
- if(s != NULL) {
- *lsi = preloads[i];
+ for (int i = 0; gLdPreloads[i] != NULL; i++) {
+ s = soinfo_elf_lookup(gLdPreloads[i], elf_hash, name);
+ if (s != NULL) {
+ *lsi = gLdPreloads[i];
goto done;
}
}
- for(i = 0; needed[i] != NULL; i++) {
+ for (int i = 0; needed[i] != NULL; i++) {
DEBUG("%s: looking up %s in %s\n",
si->name, name, needed[i]->name);
s = soinfo_elf_lookup(needed[i], elf_hash, name);
@@ -578,7 +572,7 @@
}
done:
- if(s != NULL) {
+ if (s != NULL) {
TRACE_TYPE(LOOKUP, "si %s sym %s s->st_value = 0x%08x, "
"found in %s, base = 0x%08x, load bias = 0x%08x\n",
si->name, name, s->st_value,
@@ -589,17 +583,26 @@
return NULL;
}
-/* This is used by dl_sym(). It performs symbol lookup only within the
+/* This is used by dlsym(3). It performs symbol lookup only within the
specified soinfo object and not in any of its dependencies.
+
+ TODO: Only looking in the specified soinfo seems wrong. dlsym(3) says
+ that it should do a breadth first search through the dependency
+ tree. This agrees with the ELF spec (aka System V Application
+ Binary Interface) where in Chapter 5 it discuss resolving "Shared
+ Object Dependencies" in breadth first search order.
*/
-Elf32_Sym *soinfo_lookup(soinfo *si, const char *name)
+Elf32_Sym* dlsym_handle_lookup(soinfo* si, const char* name)
{
return soinfo_elf_lookup(si, elfhash(name), name);
}
-/* This is used by dl_sym(). It performs a global symbol lookup.
+/* This is used by dlsym(3) to performs a global symbol lookup. If the
+ start value is null (for RTLD_DEFAULT), the search starts at the
+ beginning of the global solist. Otherwise the search starts at the
+ specified soinfo (for RTLD_NEXT).
*/
-Elf32_Sym* lookup(const char* name, soinfo** found, soinfo* start) {
+Elf32_Sym* dlsym_linear_lookup(const char* name, soinfo** found, soinfo* start) {
unsigned elf_hash = elfhash(name);
if (start == NULL) {
@@ -623,31 +626,25 @@
return s;
}
-soinfo *find_containing_library(const void *addr)
-{
- soinfo *si;
-
- for(si = solist; si != NULL; si = si->next)
- {
- if((unsigned)addr >= si->base && (unsigned)addr - si->base < si->size) {
+soinfo* find_containing_library(const void* addr) {
+ for (soinfo* si = solist; si != NULL; si = si->next) {
+ if ((unsigned)addr >= si->base && (unsigned)addr - si->base < si->size) {
return si;
}
}
-
return NULL;
}
-Elf32_Sym *soinfo_find_symbol(soinfo* si, const void *addr)
-{
+Elf32_Sym* dladdr_find_symbol(soinfo* si, const void* addr) {
unsigned int i;
unsigned soaddr = (unsigned)addr - si->base;
/* Search the library's symbol table for any defined symbol which
* contains this address */
- for(i=0; i<si->nchain; i++) {
+ for (i=0; i<si->nchain; i++) {
Elf32_Sym *sym = &si->symtab[i];
- if(sym->st_shndx != SHN_UNDEF &&
+ if (sym->st_shndx != SHN_UNDEF &&
soaddr >= sym->st_value &&
soaddr < sym->st_value + sym->st_size) {
return sym;
@@ -658,12 +655,10 @@
}
#if 0
-static void dump(soinfo *si)
+static void dump(soinfo* si)
{
- Elf32_Sym *s = si->symtab;
- unsigned n;
-
- for(n = 0; n < si->nchain; n++) {
+ Elf32_Sym* s = si->symtab;
+ for (unsigned n = 0; n < si->nchain; n++) {
TRACE("%04d> %08x: %02x %04x %08x %08x %s\n", n, s,
s->st_info, s->st_shndx, s->st_value, s->st_size,
si->strtab + s->st_name);
@@ -708,197 +703,34 @@
return fd;
}
-// Returns 'true' if the library is prelinked or on failure so we error out
-// either way. We no longer support prelinking.
-static bool is_prelinked(int fd, const char* name)
-{
- struct prelink_info_t {
- long mmap_addr;
- char tag[4]; // "PRE ".
- };
-
- off_t sz = lseek(fd, -sizeof(prelink_info_t), SEEK_END);
- if (sz < 0) {
- DL_ERR("lseek failed: %s", strerror(errno));
- return true;
- }
-
- prelink_info_t info;
- int rc = TEMP_FAILURE_RETRY(read(fd, &info, sizeof(info)));
- if (rc != sizeof(info)) {
- DL_ERR("could not read prelink_info_t structure for \"%s\": %s", name, strerror(errno));
- return true;
- }
-
- if (memcmp(info.tag, "PRE ", 4) == 0) {
- DL_ERR("prelinked libraries no longer supported: %s", name);
- return true;
- }
- return false;
-}
-
-/* verify_elf_header
- * Verifies the content of an ELF header.
- *
- * Args:
- *
- * Returns:
- * 0 on success
- * -1 if no valid ELF object is found @ base.
- */
-static int
-verify_elf_header(const Elf32_Ehdr* hdr)
-{
- if (hdr->e_ident[EI_MAG0] != ELFMAG0) return -1;
- if (hdr->e_ident[EI_MAG1] != ELFMAG1) return -1;
- if (hdr->e_ident[EI_MAG2] != ELFMAG2) return -1;
- if (hdr->e_ident[EI_MAG3] != ELFMAG3) return -1;
- if (hdr->e_type != ET_DYN) return -1;
-
- /* TODO: Should we verify anything else in the header? */
-#ifdef ANDROID_ARM_LINKER
- if (hdr->e_machine != EM_ARM) return -1;
-#elif defined(ANDROID_X86_LINKER)
- if (hdr->e_machine != EM_386) return -1;
-#elif defined(ANDROID_MIPS_LINKER)
- if (hdr->e_machine != EM_MIPS) return -1;
-#endif
- return 0;
-}
-
-struct scoped_fd {
- ~scoped_fd() {
- if (fd != -1) {
- close(fd);
- }
- }
- int fd;
-};
-
-struct soinfo_ptr {
- soinfo_ptr(const char* name) {
- const char* bname = strrchr(name, '/');
- ptr = soinfo_alloc(bname ? bname + 1 : name);
- }
- ~soinfo_ptr() {
- soinfo_free(ptr);
- }
- soinfo* release() {
- soinfo* result = ptr;
- ptr = NULL;
- return result;
- }
- soinfo* ptr;
-};
-
-// TODO: rewrite linker_phdr.h to use a class, then lose this.
-struct phdr_ptr {
- phdr_ptr() : phdr_mmap(NULL) {}
- ~phdr_ptr() {
- if (phdr_mmap != NULL) {
- phdr_table_unload(phdr_mmap, phdr_size);
- }
- }
- void* phdr_mmap;
- Elf32_Addr phdr_size;
-};
-
static soinfo* load_library(const char* name) {
// Open the file.
- scoped_fd fd;
- fd.fd = open_library(name);
- if (fd.fd == -1) {
+ int fd = open_library(name);
+ if (fd == -1) {
DL_ERR("library \"%s\" not found", name);
return NULL;
}
- // Read the ELF header.
- Elf32_Ehdr header[1];
- int ret = TEMP_FAILURE_RETRY(read(fd.fd, (void*)header, sizeof(header)));
- if (ret < 0) {
- DL_ERR("can't read file \"%s\": %s", name, strerror(errno));
- return NULL;
- }
- if (ret != (int)sizeof(header)) {
- DL_ERR("too small to be an ELF executable: %s", name);
- return NULL;
- }
- if (verify_elf_header(header) < 0) {
- DL_ERR("not a valid ELF executable: %s", name);
+ // Read the ELF header and load the segments.
+ ElfReader elf_reader(name, fd);
+ if (!elf_reader.Load()) {
return NULL;
}
- // Read the program header table.
- const Elf32_Phdr* phdr_table;
- phdr_ptr phdr_holder;
- ret = phdr_table_load(fd.fd, header->e_phoff, header->e_phnum,
- &phdr_holder.phdr_mmap, &phdr_holder.phdr_size, &phdr_table);
- if (ret < 0) {
- DL_ERR("can't load program header table: %s: %s", name, strerror(errno));
+ const char* bname = strrchr(name, '/');
+ soinfo* si = soinfo_alloc(bname ? bname + 1 : name);
+ if (si == NULL) {
return NULL;
}
- size_t phdr_count = header->e_phnum;
-
- // Get the load extents.
- Elf32_Addr ext_sz = phdr_table_get_load_size(phdr_table, phdr_count);
- TRACE("[ '%s' wants sz=0x%08x ]\n", name, ext_sz);
- if (ext_sz == 0) {
- DL_ERR("no loadable segments in file: %s", name);
- return NULL;
- }
-
- // We no longer support pre-linked libraries.
- if (is_prelinked(fd.fd, name)) {
- return NULL;
- }
-
- // Reserve address space for all loadable segments.
- void* load_start = NULL;
- Elf32_Addr load_size = 0;
- Elf32_Addr load_bias = 0;
- ret = phdr_table_reserve_memory(phdr_table,
- phdr_count,
- &load_start,
- &load_size,
- &load_bias);
- if (ret < 0) {
- DL_ERR("can't reserve %d bytes in address space for \"%s\": %s",
- ext_sz, name, strerror(errno));
- return NULL;
- }
-
- TRACE("[ allocated memory for %s @ %p (0x%08x) ]\n", 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_bias,
- fd.fd);
- if (ret < 0) {
- DL_ERR("can't map loadable segments for \"%s\": %s",
- name, strerror(errno));
- return NULL;
- }
-
- soinfo_ptr si(name);
- if (si.ptr == NULL) {
- return NULL;
- }
-
- si.ptr->base = (Elf32_Addr) load_start;
- si.ptr->size = load_size;
- si.ptr->load_bias = load_bias;
- si.ptr->flags = 0;
- si.ptr->entry = 0;
- si.ptr->dynamic = (unsigned *)-1;
- si.ptr->phnum = phdr_count;
- si.ptr->phdr = phdr_table_get_loaded_phdr(phdr_table, phdr_count, load_bias);
- if (si.ptr->phdr == NULL) {
- DL_ERR("can't find loaded PHDR for \"%s\"", name);
- return NULL;
- }
-
- return si.release();
+ si->base = elf_reader.load_start();
+ si->size = elf_reader.load_size();
+ si->load_bias = elf_reader.load_bias();
+ si->flags = 0;
+ si->entry = 0;
+ si->dynamic = NULL;
+ si->phnum = elf_reader.phdr_count();
+ si->phdr = elf_reader.loaded_phdr();
+ return si;
}
static soinfo *find_loaded_library(const char *name)
@@ -912,8 +744,8 @@
bname = strrchr(name, '/');
bname = bname ? bname + 1 : name;
- for(si = solist; si != NULL; si = si->next){
- if(!strcmp(bname, si->name)) {
+ for (si = solist; si != NULL; si = si->next) {
+ if (!strcmp(bname, si->name)) {
return si;
}
}
@@ -967,9 +799,10 @@
TRACE("unloading '%s'\n", si->name);
si->CallDestructors();
- for (unsigned* d = si->dynamic; *d; d += 2) {
- if (d[0] == DT_NEEDED) {
- soinfo* lsi = find_loaded_library(si->strtab + d[1]);
+ for (Elf32_Dyn* d = si->dynamic; d->d_tag != DT_NEEDED; ++d) {
+ if (d->d_tag == DT_NEEDED) {
+ const char* library_name = si->strtab + d->d_un.d_val;
+ soinfo* lsi = find_loaded_library(library_name);
if (lsi != NULL) {
TRACE("%s needs to unload %s\n", si->name, lsi->name);
soinfo_unload(lsi);
@@ -1022,30 +855,30 @@
* ideal. They should probably be either uint32_t, Elf32_Addr, or unsigned
* long.
*/
-static int soinfo_relocate(soinfo *si, Elf32_Rel *rel, unsigned count,
- soinfo *needed[])
+static int soinfo_relocate(soinfo* si, Elf32_Rel* rel, unsigned count,
+ soinfo* needed[])
{
- Elf32_Sym *symtab = si->symtab;
- const char *strtab = si->strtab;
- Elf32_Sym *s;
- Elf32_Rel *start = rel;
- soinfo *lsi;
+ Elf32_Sym* symtab = si->symtab;
+ const char* strtab = si->strtab;
+ Elf32_Sym* s;
+ Elf32_Rel* start = rel;
+ soinfo* lsi;
for (size_t idx = 0; idx < count; ++idx, ++rel) {
unsigned type = ELF32_R_TYPE(rel->r_info);
unsigned sym = ELF32_R_SYM(rel->r_info);
unsigned reloc = (unsigned)(rel->r_offset + si->load_bias);
unsigned sym_addr = 0;
- char *sym_name = NULL;
+ char* sym_name = NULL;
DEBUG("Processing '%s' relocation at index %d\n", si->name, idx);
if (type == 0) { // R_*_NONE
continue;
}
- if(sym != 0) {
+ if (sym != 0) {
sym_name = (char *)(strtab + symtab[sym].st_name);
s = soinfo_do_lookup(si, sym_name, &lsi, needed);
- if(s == NULL) {
+ if (s == NULL) {
/* We only allow an undefined symbol if this is a weak
reference.. */
s = &symtab[sym];
@@ -1103,7 +936,7 @@
} else {
/* We got a definition. */
#if 0
- if((base == 0) && (si->base != 0)){
+ if ((base == 0) && (si->base != 0)) {
/* linking from libraries to main image is bad */
DL_ERR("cannot locate \"%s\"...",
strtab + symtab[sym].st_name);
@@ -1300,9 +1133,9 @@
sym = symtab + gotsym;
got = si->plt_got + local_gotno;
for (g = gotsym; g < symtabno; g++, sym++, got++) {
- const char *sym_name;
- Elf32_Sym *s;
- soinfo *lsi;
+ const char* sym_name;
+ Elf32_Sym* s;
+ soinfo* lsi;
/* This is an undefined reference... try to locate it */
sym_name = si->strtab + sym->st_name;
@@ -1407,10 +1240,11 @@
return;
}
- if (dynamic) {
- for (unsigned* d = dynamic; *d; d += 2) {
- if (d[0] == DT_NEEDED) {
- soinfo* lsi = find_loaded_library(strtab + d[1]);
+ if (dynamic != NULL) {
+ for (Elf32_Dyn* d = dynamic; d->d_tag != DT_NULL; ++d) {
+ if (d->d_tag == DT_NEEDED) {
+ const char* library_name = strtab + d->d_un.d_val;
+ soinfo* lsi = find_loaded_library(library_name);
if (lsi == NULL) {
DL_ERR("\"%s\": could not initialize dependent library", name);
} else {
@@ -1495,8 +1329,7 @@
Elf32_Addr base = si->load_bias;
const Elf32_Phdr *phdr = si->phdr;
int phnum = si->phnum;
- int relocating_linker = (si->flags & FLAG_LINKER) != 0;
- soinfo **needed, **pneeded;
+ bool relocating_linker = (si->flags & FLAG_LINKER) != 0;
/* We can't debug anything until the linker is relocated */
if (!relocating_linker) {
@@ -1526,81 +1359,82 @@
#endif
/* extract useful information from dynamic section */
- for (unsigned* d = si->dynamic; *d; ++d) {
- DEBUG("d = %p, d[0] = 0x%08x d[1] = 0x%08x\n", d, d[0], d[1]);
- switch(*d++){
+ uint32_t needed_count = 0;
+ for (Elf32_Dyn* d = si->dynamic; d->d_tag != DT_NULL; ++d) {
+ DEBUG("d = %p, d[0](tag) = 0x%08x d[1](val) = 0x%08x\n", d, d->d_tag, d->d_un.d_val);
+ switch(d->d_tag){
case DT_HASH:
- si->nbucket = ((unsigned *) (base + *d))[0];
- si->nchain = ((unsigned *) (base + *d))[1];
- si->bucket = (unsigned *) (base + *d + 8);
- si->chain = (unsigned *) (base + *d + 8 + si->nbucket * 4);
+ si->nbucket = ((unsigned *) (base + d->d_un.d_ptr))[0];
+ si->nchain = ((unsigned *) (base + d->d_un.d_ptr))[1];
+ si->bucket = (unsigned *) (base + d->d_un.d_ptr + 8);
+ si->chain = (unsigned *) (base + d->d_un.d_ptr + 8 + si->nbucket * 4);
break;
case DT_STRTAB:
- si->strtab = (const char *) (base + *d);
+ si->strtab = (const char *) (base + d->d_un.d_ptr);
break;
case DT_SYMTAB:
- si->symtab = (Elf32_Sym *) (base + *d);
+ si->symtab = (Elf32_Sym *) (base + d->d_un.d_ptr);
break;
case DT_PLTREL:
- if(*d != DT_REL) {
+ if (d->d_un.d_val != DT_REL) {
DL_ERR("unsupported DT_RELA in \"%s\"", si->name);
return false;
}
break;
case DT_JMPREL:
- si->plt_rel = (Elf32_Rel*) (base + *d);
+ si->plt_rel = (Elf32_Rel*) (base + d->d_un.d_ptr);
break;
case DT_PLTRELSZ:
- si->plt_rel_count = *d / 8;
+ si->plt_rel_count = d->d_un.d_val / sizeof(Elf32_Rel);
break;
case DT_REL:
- si->rel = (Elf32_Rel*) (base + *d);
+ si->rel = (Elf32_Rel*) (base + d->d_un.d_ptr);
break;
case DT_RELSZ:
- si->rel_count = *d / 8;
+ si->rel_count = d->d_un.d_val / sizeof(Elf32_Rel);
break;
case DT_PLTGOT:
/* Save this in case we decide to do lazy binding. We don't yet. */
- si->plt_got = (unsigned *)(base + *d);
+ si->plt_got = (unsigned *)(base + d->d_un.d_ptr);
break;
case DT_DEBUG:
// Set the DT_DEBUG entry to the address of _r_debug for GDB
// if the dynamic table is writable
if ((dynamic_flags & PF_W) != 0) {
- *d = (int) &_r_debug;
+ d->d_un.d_val = (int) &_r_debug;
}
break;
case DT_RELA:
DL_ERR("unsupported DT_RELA in \"%s\"", si->name);
return false;
case DT_INIT:
- si->init_func = (void (*)(void))(base + *d);
+ si->init_func = (void (*)(void))(base + d->d_un.d_ptr);
DEBUG("%s constructors (init func) found at %p\n", si->name, si->init_func);
break;
case DT_FINI:
- si->fini_func = (void (*)(void))(base + *d);
+ si->fini_func = (void (*)(void))(base + d->d_un.d_ptr);
DEBUG("%s destructors (fini func) found at %p\n", si->name, si->fini_func);
break;
case DT_INIT_ARRAY:
- si->init_array = (unsigned *)(base + *d);
+ si->init_array = (unsigned *)(base + d->d_un.d_ptr);
DEBUG("%s constructors (init_array) found at %p\n", si->name, si->init_array);
break;
case DT_INIT_ARRAYSZ:
- si->init_array_count = ((unsigned)*d) / sizeof(Elf32_Addr);
+ si->init_array_count = ((unsigned)d->d_un.d_val) / sizeof(Elf32_Addr);
break;
case DT_FINI_ARRAY:
- si->fini_array = (unsigned *)(base + *d);
+ si->fini_array = (unsigned *)(base + d->d_un.d_ptr);
DEBUG("%s destructors (fini_array) found at %p\n", si->name, si->fini_array);
break;
case DT_FINI_ARRAYSZ:
- si->fini_array_count = ((unsigned)*d) / sizeof(Elf32_Addr);
+ si->fini_array_count = ((unsigned)d->d_un.d_val) / sizeof(Elf32_Addr);
break;
case DT_PREINIT_ARRAY:
- si->preinit_array = (unsigned *)(base + *d);
+ si->preinit_array = (unsigned *)(base + d->d_un.d_ptr);
DEBUG("%s constructors (preinit_array) found at %p\n", si->name, si->preinit_array);
break;
case DT_PREINIT_ARRAYSZ:
- si->preinit_array_count = ((unsigned)*d) / sizeof(Elf32_Addr);
+ si->preinit_array_count = ((unsigned)d->d_un.d_val) / sizeof(Elf32_Addr);
break;
case DT_TEXTREL:
si->has_text_relocations = true;
@@ -1608,18 +1442,21 @@
case DT_SYMBOLIC:
si->has_DT_SYMBOLIC = true;
break;
-#if defined(DT_FLAGS)
+ case DT_NEEDED:
+ ++needed_count;
+ break;
+#if defined DT_FLAGS
+ // TODO: why is DT_FLAGS not defined?
case DT_FLAGS:
- if (*d & DF_TEXTREL) {
+ if (d->d_un.d_val & DF_TEXTREL) {
si->has_text_relocations = true;
}
- if (*d & DF_SYMBOLIC) {
+ if (d->d_un.d_val & DF_SYMBOLIC) {
si->has_DT_SYMBOLIC = true;
}
break;
#endif
#if defined(ANDROID_MIPS_LINKER)
- case DT_NEEDED:
case DT_STRSZ:
case DT_SYMENT:
case DT_RELENT:
@@ -1627,7 +1464,7 @@
case DT_MIPS_RLD_MAP:
// Set the DT_MIPS_RLD_MAP entry to the address of _r_debug for GDB.
{
- r_debug** dp = (r_debug**) *d;
+ r_debug** dp = (r_debug**) d->d_un.d_ptr;
*dp = &_r_debug;
}
break;
@@ -1638,19 +1475,19 @@
break;
case DT_MIPS_SYMTABNO:
- si->mips_symtabno = *d;
+ si->mips_symtabno = d->d_un.d_val;
break;
case DT_MIPS_LOCAL_GOTNO:
- si->mips_local_gotno = *d;
+ si->mips_local_gotno = d->d_un.d_val;
break;
case DT_MIPS_GOTSYM:
- si->mips_gotsym = *d;
+ si->mips_gotsym = d->d_un.d_val;
break;
default:
- DEBUG("Unused DT entry: type 0x%08x arg 0x%08x\n", d[-1], d[0]);
+ DEBUG("Unused DT entry: type 0x%08x arg 0x%08x\n", d->d_tag, d->d_un.d_val);
break;
#endif
}
@@ -1660,6 +1497,10 @@
si->base, si->strtab, si->symtab);
// Sanity checks.
+ if (relocating_linker && needed_count != 0) {
+ DL_ERR("linker cannot have DT_NEEDED dependencies on other libraries");
+ return false;
+ }
if (si->nbucket == 0) {
DL_ERR("empty/missing DT_HASH in \"%s\" (built with --hash-style=gnu?)", si->name);
return false;
@@ -1675,30 +1516,31 @@
/* if this is the main executable, then load all of the preloads now */
if (si->flags & FLAG_EXE) {
- memset(preloads, 0, sizeof(preloads));
+ memset(gLdPreloads, 0, sizeof(gLdPreloads));
for (size_t i = 0; gLdPreloadNames[i] != NULL; i++) {
soinfo* lsi = find_library(gLdPreloadNames[i]);
if (lsi == NULL) {
- strlcpy(tmp_err_buf, linker_get_error(), sizeof(tmp_err_buf));
+ strlcpy(tmp_err_buf, linker_get_error_buffer(), sizeof(tmp_err_buf));
DL_ERR("could not load library \"%s\" needed by \"%s\"; caused by %s",
gLdPreloadNames[i], si->name, tmp_err_buf);
return false;
}
- preloads[i] = lsi;
+ gLdPreloads[i] = lsi;
}
}
- /* dynamic_count is an upper bound for the number of needed libs */
- pneeded = needed = (soinfo**) alloca((1 + dynamic_count) * sizeof(soinfo*));
+ soinfo** needed = (soinfo**) alloca((1 + needed_count) * sizeof(soinfo*));
+ soinfo** pneeded = needed;
- for (unsigned* d = si->dynamic; *d; d += 2) {
- if (d[0] == DT_NEEDED) {
- DEBUG("%s needs %s\n", si->name, si->strtab + d[1]);
- soinfo* lsi = find_library(si->strtab + d[1]);
+ for (Elf32_Dyn* d = si->dynamic; d->d_tag != DT_NULL; ++d) {
+ if (d->d_tag == DT_NEEDED) {
+ const char* library_name = si->strtab + d->d_un.d_val;
+ DEBUG("%s needs %s\n", si->name, library_name);
+ soinfo* lsi = find_library(library_name);
if (lsi == NULL) {
- strlcpy(tmp_err_buf, linker_get_error(), sizeof(tmp_err_buf));
+ strlcpy(tmp_err_buf, linker_get_error_buffer(), sizeof(tmp_err_buf));
DL_ERR("could not load library \"%s\" needed by \"%s\"; caused by %s",
- si->strtab + d[1], si->name, tmp_err_buf);
+ library_name, si->name, tmp_err_buf);
return false;
}
*pneeded++ = lsi;
@@ -1719,15 +1561,15 @@
}
}
- if (si->plt_rel) {
+ if (si->plt_rel != NULL) {
DEBUG("[ relocating %s plt ]\n", si->name );
- if(soinfo_relocate(si, si->plt_rel, si->plt_rel_count, needed)) {
+ if (soinfo_relocate(si, si->plt_rel, si->plt_rel_count, needed)) {
return false;
}
}
- if (si->rel) {
+ if (si->rel != NULL) {
DEBUG("[ relocating %s ]\n", si->name );
- if(soinfo_relocate(si, si->rel, si->rel_count, needed)) {
+ if (soinfo_relocate(si, si->rel, si->rel_count, needed)) {
return false;
}
}
@@ -1791,12 +1633,12 @@
// Initialize environment functions, and get to the ELF aux vectors table.
linker_env_init(args);
- debugger_init();
+ debuggerd_init();
// Get a few environment variables.
const char* LD_DEBUG = linker_env_get("LD_DEBUG");
if (LD_DEBUG != NULL) {
- debug_verbosity = atoi(LD_DEBUG);
+ gLdDebugVerbosity = atoi(LD_DEBUG);
}
// Normally, these are cleaned by linker_env_init, but the test
@@ -1827,29 +1669,31 @@
_r_debug.r_map = map;
r_debug_tail = map;
- /* gdb expects the linker to be in the debug shared object list.
- * Without this, gdb has trouble locating the linker's ".text"
- * and ".plt" sections. Gdb could also potentially use this to
- * relocate the offset of our exported 'rtld_db_dlactivity' symbol.
- * Don't use soinfo_alloc(), because the linker shouldn't
- * be on the soinfo list.
- */
- static soinfo linker_soinfo;
- strlcpy(linker_soinfo.name, "/system/bin/linker", sizeof(linker_soinfo.name));
- linker_soinfo.flags = 0;
- linker_soinfo.base = linker_base;
-
- /*
- * Set the dynamic field in the link map otherwise gdb will complain with
- * the following:
- * warning: .dynamic section for "/system/bin/linker" is not at the
- * expected address (wrong library or version mismatch?)
+ /* gdb expects the linker to be in the debug shared object list.
+ * Without this, gdb has trouble locating the linker's ".text"
+ * and ".plt" sections. Gdb could also potentially use this to
+ * relocate the offset of our exported 'rtld_db_dlactivity' symbol.
+ * Don't use soinfo_alloc(), because the linker shouldn't
+ * be on the soinfo list.
*/
- Elf32_Ehdr *elf_hdr = (Elf32_Ehdr *) linker_base;
- Elf32_Phdr *phdr = (Elf32_Phdr*)((unsigned char*) linker_base + elf_hdr->e_phoff);
- phdr_table_get_dynamic_section(phdr, elf_hdr->e_phnum, linker_base,
- &linker_soinfo.dynamic, NULL, NULL);
- insert_soinfo_into_debug_map(&linker_soinfo);
+ {
+ static soinfo linker_soinfo;
+ strlcpy(linker_soinfo.name, "/system/bin/linker", sizeof(linker_soinfo.name));
+ linker_soinfo.flags = 0;
+ linker_soinfo.base = linker_base;
+
+ /*
+ * Set the dynamic field in the link map otherwise gdb will complain with
+ * the following:
+ * warning: .dynamic section for "/system/bin/linker" is not at the
+ * expected address (wrong library or version mismatch?)
+ */
+ Elf32_Ehdr *elf_hdr = (Elf32_Ehdr *) linker_base;
+ Elf32_Phdr *phdr = (Elf32_Phdr*)((unsigned char*) linker_base + elf_hdr->e_phoff);
+ phdr_table_get_dynamic_section(phdr, elf_hdr->e_phnum, linker_base,
+ &linker_soinfo.dynamic, NULL, NULL);
+ insert_soinfo_into_debug_map(&linker_soinfo);
+ }
// Extract information passed from the kernel.
si->phdr = reinterpret_cast<Elf32_Phdr*>(args.getauxval(AT_PHDR));
@@ -1870,7 +1714,7 @@
break;
}
}
- si->dynamic = (unsigned *)-1;
+ si->dynamic = NULL;
si->refcount = 1;
// Use LD_LIBRARY_PATH and LD_PRELOAD (but only if we aren't setuid/setgid).
@@ -1880,22 +1724,20 @@
somain = si;
if (!soinfo_link_image(si)) {
- const char* msg = "CANNOT LINK EXECUTABLE\n";
- write(2, __linker_dl_err_buf, strlen(__linker_dl_err_buf));
- write(2, msg, strlen(msg));
+ __libc_format_fd(2, "CANNOT LINK EXECUTABLE: %s\n", linker_get_error_buffer());
exit(EXIT_FAILURE);
}
si->CallPreInitConstructors();
- for (size_t i = 0; preloads[i] != NULL; ++i) {
- preloads[i]->CallConstructors();
+ for (size_t i = 0; gLdPreloads[i] != NULL; ++i) {
+ gLdPreloads[i]->CallConstructors();
}
- /*After the link_image, the si->load_bias is initialized.
- *For so lib, the map->l_addr will be updated in notify_gdb_of_load.
- *We need to update this value for so exe here. So Unwind_Backtrace
- *for some arch like x86 could work correctly within so exe.
+ /* After the link_image, the si->load_bias is initialized.
+ * For so lib, the map->l_addr will be updated in notify_gdb_of_load.
+ * We need to update this value for so exe here. So Unwind_Backtrace
+ * for some arch like x86 could work correctly within so exe.
*/
map->l_addr = si->load_bias;
si->CallConstructors();
@@ -1919,11 +1761,13 @@
unsigned n;
unsigned i;
unsigned count = 0;
- for(n = 0; n < 4096; n++){
- if(bitmask[n]){
+ for (n = 0; n < 4096; n++) {
+ if (bitmask[n]) {
unsigned x = bitmask[n];
- for(i = 0; i < 8; i++){
- if(x & 1) count++;
+ for (i = 0; i < 8; i++) {
+ if (x & 1) {
+ count++;
+ }
x >>= 1;
}
}
@@ -1989,7 +1833,7 @@
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.dynamic = NULL;
linker_so.phdr = phdr;
linker_so.phnum = elf_hdr->e_phnum;
linker_so.flags |= FLAG_LINKER;
diff --git a/linker/linker.h b/linker/linker.h
index cf6fff9..cef6905 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -36,6 +36,15 @@
#include <link.h>
+#include <private/debug_format.h>
+
+#define DL_ERR(fmt, x...) \
+ do { \
+ __libc_format_buffer(linker_get_error_buffer(), linker_get_error_buffer_size(), fmt, ##x); \
+ /* If LD_DEBUG is set high enough, log every dlerror(3) message. */ \
+ DEBUG("%s\n", linker_get_error_buffer()); \
+ } while(0)
+
// Returns the address of the page containing address 'x'.
#define PAGE_START(x) ((x) & PAGE_MASK)
@@ -50,10 +59,10 @@
struct link_map {
uintptr_t l_addr;
- char * l_name;
+ char* l_name;
uintptr_t l_ld;
- struct link_map * l_next;
- struct link_map * l_prev;
+ struct link_map* l_next;
+ struct link_map* l_prev;
};
// Values for r_debug->state
@@ -87,7 +96,7 @@
int unused; // DO NOT USE, maintained for compatibility.
- unsigned* dynamic;
+ Elf32_Dyn* dynamic;
unsigned unused2; // DO NOT USE, maintained for compatibility
unsigned unused3; // DO NOT USE, maintained for compatibility
@@ -167,14 +176,16 @@
soinfo* do_dlopen(const char* name, int flags);
int do_dlclose(soinfo* si);
-Elf32_Sym* lookup(const char* name, soinfo** found, soinfo* start);
+Elf32_Sym* dlsym_linear_lookup(const char* name, soinfo** found, soinfo* start);
soinfo* find_containing_library(const void* addr);
-const char* linker_get_error();
-Elf32_Sym* soinfo_find_symbol(soinfo* si, const void* addr);
-Elf32_Sym* soinfo_lookup(soinfo* si, const char* name);
+Elf32_Sym* dladdr_find_symbol(soinfo* si, const void* addr);
+Elf32_Sym* dlsym_handle_lookup(soinfo* si, const char* name);
-void debugger_init();
+void debuggerd_init();
extern "C" void notify_gdb_of_libraries();
+char* linker_get_error_buffer();
+size_t linker_get_error_buffer_size();
+
#endif
diff --git a/linker/linker_debug.h b/linker/linker_debug.h
index b326d00..bf9ef92 100644
--- a/linker/linker_debug.h
+++ b/linker/linker_debug.h
@@ -54,15 +54,17 @@
#include <private/debug_format.h>
+__LIBC_HIDDEN__ extern int gLdDebugVerbosity;
+
#if LINKER_DEBUG_TO_LOG
#define _PRINTVF(v,x...) \
do { \
- if (debug_verbosity > (v)) __libc_format_log(5-(v),"linker",x); \
+ if (gLdDebugVerbosity > (v)) __libc_format_log(5-(v),"linker",x); \
} while (0)
#else /* !LINKER_DEBUG_TO_LOG */
#define _PRINTVF(v,x...) \
do { \
- if (debug_verbosity > (v)) __libc_format_fd(1, x); \
+ if (gLdDebugVerbosity > (v)) __libc_format_fd(1, x); \
} while (0)
#endif /* !LINKER_DEBUG_TO_LOG */
diff --git a/linker/linker_phdr.cpp b/linker/linker_phdr.cpp
index 94260fa..64dbb70 100644
--- a/linker/linker_phdr.cpp
+++ b/linker/linker_phdr.cpp
@@ -26,10 +26,13 @@
* SUCH DAMAGE.
*/
+#include "linker_phdr.h"
+
#include <errno.h>
#include <sys/mman.h>
-#include "linker_phdr.h"
+#include "linker.h"
+#include "linker_debug.h"
/**
TECHNICAL NOTE ON ELF LOADING.
@@ -112,66 +115,116 @@
MAYBE_MAP_FLAG((x), PF_R, PROT_READ) | \
MAYBE_MAP_FLAG((x), PF_W, PROT_WRITE))
-/* Load the program header table from an ELF file into a read-only private
- * anonymous mmap-ed block.
- *
- * Input:
- * fd -> file descriptor
- * phdr_offset -> file offset of phdr table
- * phdr_num -> number of entries in the table.
- *
- * Output:
- * phdr_mmap -> address of mmap block in memory.
- * phdr_memsize -> size of mmap block in memory.
- * phdr_table -> address of first entry in memory.
- *
- * Return:
- * -1 on error, or 0 on success.
- */
-int phdr_table_load(int fd,
- Elf32_Addr phdr_offset,
- Elf32_Half phdr_num,
- void** phdr_mmap,
- Elf32_Addr* phdr_size,
- const Elf32_Phdr** phdr_table)
-{
- Elf32_Addr page_min, page_max, page_offset;
- void* mmap_result;
-
- /* Just like the kernel, we only accept program header tables that
- * are smaller than 64KB. */
- if (phdr_num < 1 || phdr_num > 65536/sizeof(Elf32_Phdr)) {
- errno = EINVAL;
- return -1;
- }
-
- page_min = PAGE_START(phdr_offset);
- page_max = PAGE_END(phdr_offset + phdr_num*sizeof(Elf32_Phdr));
- page_offset = PAGE_OFFSET(phdr_offset);
-
- mmap_result = mmap(NULL,
- page_max - page_min,
- PROT_READ,
- MAP_PRIVATE,
- fd,
- page_min);
-
- if (mmap_result == MAP_FAILED) {
- return -1;
- }
-
- *phdr_mmap = mmap_result;
- *phdr_size = page_max - page_min;
- *phdr_table = (Elf32_Phdr*)((char*)mmap_result + page_offset);
-
- return 0;
+ElfReader::ElfReader(const char* name, int fd)
+ : name_(name), fd_(fd),
+ phdr_num_(0), phdr_mmap_(NULL), phdr_table_(NULL), phdr_size_(0),
+ load_start_(NULL), load_size_(0), load_bias_(0),
+ loaded_phdr_(NULL) {
}
-void phdr_table_unload(void* phdr_mmap, Elf32_Addr phdr_memsize)
-{
- munmap(phdr_mmap, phdr_memsize);
+ElfReader::~ElfReader() {
+ if (fd_ != -1) {
+ close(fd_);
+ }
+ if (phdr_mmap_ != NULL) {
+ munmap(phdr_mmap_, phdr_size_);
+ }
}
+bool ElfReader::Load() {
+ return ReadElfHeader() &&
+ VerifyElfHeader() &&
+ ReadProgramHeader() &&
+ ReserveAddressSpace() &&
+ LoadSegments() &&
+ FindPhdr();
+}
+
+bool ElfReader::ReadElfHeader() {
+ ssize_t rc = TEMP_FAILURE_RETRY(read(fd_, &header_, sizeof(header_)));
+ if (rc < 0) {
+ DL_ERR("can't read file \"%s\": %s", name_, strerror(errno));
+ return false;
+ }
+ if (rc != sizeof(header_)) {
+ DL_ERR("\"%s\" is too small to be an ELF executable", name_);
+ return false;
+ }
+ return true;
+}
+
+bool ElfReader::VerifyElfHeader() {
+ if (header_.e_ident[EI_MAG0] != ELFMAG0 ||
+ header_.e_ident[EI_MAG1] != ELFMAG1 ||
+ header_.e_ident[EI_MAG2] != ELFMAG2 ||
+ header_.e_ident[EI_MAG3] != ELFMAG3) {
+ DL_ERR("\"%s\" has bad ELF magic", name_);
+ return false;
+ }
+
+ if (header_.e_ident[EI_CLASS] != ELFCLASS32) {
+ DL_ERR("\"%s\" not 32-bit: %d", name_, header_.e_ident[EI_CLASS]);
+ return false;
+ }
+ if (header_.e_ident[EI_DATA] != ELFDATA2LSB) {
+ DL_ERR("\"%s\" not little-endian: %d", name_, header_.e_ident[EI_DATA]);
+ return false;
+ }
+
+ if (header_.e_type != ET_DYN) {
+ DL_ERR("\"%s\" has unexpected e_type: %d", name_, header_.e_type);
+ return false;
+ }
+
+ if (header_.e_version != EV_CURRENT) {
+ DL_ERR("\"%s\" has unexpected e_version: %d", name_, header_.e_version);
+ return false;
+ }
+
+ if (header_.e_machine !=
+#ifdef ANDROID_ARM_LINKER
+ EM_ARM
+#elif defined(ANDROID_MIPS_LINKER)
+ EM_MIPS
+#elif defined(ANDROID_X86_LINKER)
+ EM_386
+#endif
+ ) {
+ DL_ERR("\"%s\" has unexpected e_machine: %d", name_, header_.e_machine);
+ return false;
+ }
+
+ return true;
+}
+
+// Loads the program header table from an ELF file into a read-only private
+// anonymous mmap-ed block.
+bool ElfReader::ReadProgramHeader() {
+ phdr_num_ = header_.e_phnum;
+
+ // Like the kernel, we only accept program header tables that
+ // are smaller than 64KiB.
+ if (phdr_num_ < 1 || phdr_num_ > 65536/sizeof(Elf32_Phdr)) {
+ DL_ERR("\"%s\" has invalid e_phnum: %d", name_, phdr_num_);
+ return false;
+ }
+
+ Elf32_Addr page_min = PAGE_START(header_.e_phoff);
+ Elf32_Addr page_max = PAGE_END(header_.e_phoff + (phdr_num_ * sizeof(Elf32_Phdr)));
+ Elf32_Addr page_offset = PAGE_OFFSET(header_.e_phoff);
+
+ phdr_size_ = page_max - page_min;
+
+ void* mmap_result = mmap(NULL, phdr_size_, PROT_READ, MAP_PRIVATE, fd_, page_min);
+ if (mmap_result == MAP_FAILED) {
+ DL_ERR("\"%s\" phdr mmap failed: %s", name_, strerror(errno));
+ return false;
+ }
+
+ phdr_mmap_ = mmap_result;
+ phdr_table_ = reinterpret_cast<Elf32_Phdr*>(reinterpret_cast<char*>(mmap_result) + page_offset);
+ return true;
+}
/* Compute the extent of all loadable segments in an ELF program header
* table. This corresponds to the page-aligned size in bytes that needs to be
@@ -211,134 +264,100 @@
return max_vaddr - min_vaddr;
}
-/* Reserve a virtual address range big enough to hold all loadable
- * segments of a program header table. This is done by creating a
- * private anonymous mmap() with PROT_NONE.
- *
- * Input:
- * phdr_table -> program header table
- * phdr_count -> number of entries in the tables
- * Output:
- * load_start -> first page of reserved address space range
- * load_size -> size in bytes of reserved address space range
- * load_bias -> load bias, as described in technical note above.
- *
- * Return:
- * 0 on success, -1 otherwise. Error code in errno.
- */
-int
-phdr_table_reserve_memory(const Elf32_Phdr* phdr_table,
- size_t phdr_count,
- void** load_start,
- Elf32_Addr* load_size,
- Elf32_Addr* load_bias)
-{
- Elf32_Addr size = phdr_table_get_load_size(phdr_table, phdr_count);
- if (size == 0) {
- errno = EINVAL;
- return -1;
- }
+// Reserve a virtual address range big enough to hold all loadable
+// segments of a program header table. This is done by creating a
+// private anonymous mmap() with PROT_NONE.
+bool ElfReader::ReserveAddressSpace() {
+ load_size_ = phdr_table_get_load_size(phdr_table_, phdr_num_);
+ if (load_size_ == 0) {
+ DL_ERR("\"%s\" has no loadable segments", name_);
+ return false;
+ }
- int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS;
- void* start = mmap(NULL, size, PROT_NONE, mmap_flags, -1, 0);
- if (start == MAP_FAILED) {
- return -1;
- }
+ int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS;
+ void* start = mmap(NULL, load_size_, PROT_NONE, mmap_flags, -1, 0);
+ if (start == MAP_FAILED) {
+ DL_ERR("couldn't reserve %d bytes of address space for \"%s\"", load_size_, name_);
+ return false;
+ }
- *load_start = start;
- *load_size = size;
- *load_bias = 0;
+ load_start_ = start;
+ load_bias_ = 0;
- for (size_t i = 0; i < phdr_count; ++i) {
- const Elf32_Phdr* phdr = &phdr_table[i];
- if (phdr->p_type == PT_LOAD) {
- *load_bias = (Elf32_Addr)start - PAGE_START(phdr->p_vaddr);
- break;
- }
+ for (size_t i = 0; i < phdr_num_; ++i) {
+ const Elf32_Phdr* phdr = &phdr_table_[i];
+ if (phdr->p_type == PT_LOAD) {
+ load_bias_ = reinterpret_cast<Elf32_Addr>(start) - PAGE_START(phdr->p_vaddr);
+ break;
}
- return 0;
+ }
+ return true;
}
-/* Map all loadable segments in process' address space.
- * This assumes you already called phdr_table_reserve_memory to
- * reserve the address space range for the library.
- *
- * Input:
- * phdr_table -> program header table
- * phdr_count -> number of entries in the table
- * load_bias -> load offset.
- * fd -> input file descriptor.
- *
- * Return:
- * 0 on success, -1 otherwise. Error code in errno.
- */
-int
-phdr_table_load_segments(const Elf32_Phdr* phdr_table,
- int phdr_count,
- Elf32_Addr load_bias,
- int fd)
-{
- int nn;
+// Map all loadable segments in process' address space.
+// This assumes you already called phdr_table_reserve_memory to
+// reserve the address space range for the library.
+// TODO: assert assumption.
+bool ElfReader::LoadSegments() {
+ for (size_t i = 0; i < phdr_num_; ++i) {
+ const Elf32_Phdr* phdr = &phdr_table_[i];
- for (nn = 0; nn < phdr_count; nn++) {
- const Elf32_Phdr* phdr = &phdr_table[nn];
- void* seg_addr;
-
- if (phdr->p_type != PT_LOAD)
- continue;
-
- /* Segment addresses in memory */
- Elf32_Addr seg_start = phdr->p_vaddr + load_bias;
- Elf32_Addr seg_end = seg_start + phdr->p_memsz;
-
- Elf32_Addr seg_page_start = PAGE_START(seg_start);
- Elf32_Addr seg_page_end = PAGE_END(seg_end);
-
- Elf32_Addr seg_file_end = seg_start + phdr->p_filesz;
-
- /* File offsets */
- Elf32_Addr file_start = phdr->p_offset;
- Elf32_Addr file_end = file_start + phdr->p_filesz;
-
- Elf32_Addr file_page_start = PAGE_START(file_start);
-
- seg_addr = mmap((void*)seg_page_start,
- file_end - file_page_start,
- PFLAGS_TO_PROT(phdr->p_flags),
- MAP_FIXED|MAP_PRIVATE,
- fd,
- file_page_start);
-
- if (seg_addr == MAP_FAILED) {
- return -1;
- }
-
- /* if the segment is writable, and does not end on a page boundary,
- * zero-fill it until the page limit. */
- if ((phdr->p_flags & PF_W) != 0 && PAGE_OFFSET(seg_file_end) > 0) {
- memset((void*)seg_file_end, 0, PAGE_SIZE - PAGE_OFFSET(seg_file_end));
- }
-
- seg_file_end = PAGE_END(seg_file_end);
-
- /* seg_file_end is now the first page address after the file
- * content. If seg_end is larger, we need to zero anything
- * between them. This is done by using a private anonymous
- * map for all extra pages.
- */
- if (seg_page_end > seg_file_end) {
- void* zeromap = mmap((void*)seg_file_end,
- seg_page_end - seg_file_end,
- PFLAGS_TO_PROT(phdr->p_flags),
- MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE,
- -1,
- 0);
- if (zeromap == MAP_FAILED) {
- return -1;
- }
- }
+ if (phdr->p_type != PT_LOAD) {
+ continue;
}
- return 0;
+
+ // Segment addresses in memory.
+ Elf32_Addr seg_start = phdr->p_vaddr + load_bias_;
+ Elf32_Addr seg_end = seg_start + phdr->p_memsz;
+
+ Elf32_Addr seg_page_start = PAGE_START(seg_start);
+ Elf32_Addr seg_page_end = PAGE_END(seg_end);
+
+ Elf32_Addr seg_file_end = seg_start + phdr->p_filesz;
+
+ // File offsets.
+ Elf32_Addr file_start = phdr->p_offset;
+ Elf32_Addr file_end = file_start + phdr->p_filesz;
+
+ Elf32_Addr file_page_start = PAGE_START(file_start);
+
+ void* seg_addr = mmap((void*)seg_page_start,
+ file_end - file_page_start,
+ PFLAGS_TO_PROT(phdr->p_flags),
+ MAP_FIXED|MAP_PRIVATE,
+ fd_,
+ file_page_start);
+ if (seg_addr == MAP_FAILED) {
+ DL_ERR("couldn't map \"%s\" segment %d: %s", name_, i, strerror(errno));
+ return false;
+ }
+
+ // if the segment is writable, and does not end on a page boundary,
+ // zero-fill it until the page limit.
+ if ((phdr->p_flags & PF_W) != 0 && PAGE_OFFSET(seg_file_end) > 0) {
+ memset((void*)seg_file_end, 0, PAGE_SIZE - PAGE_OFFSET(seg_file_end));
+ }
+
+ seg_file_end = PAGE_END(seg_file_end);
+
+ // seg_file_end is now the first page address after the file
+ // content. If seg_end is larger, we need to zero anything
+ // between them. This is done by using a private anonymous
+ // map for all extra pages.
+ if (seg_page_end > seg_file_end) {
+ void* zeromap = mmap((void*)seg_file_end,
+ seg_page_end - seg_file_end,
+ PFLAGS_TO_PROT(phdr->p_flags),
+ MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE,
+ -1,
+ 0);
+ if (zeromap == MAP_FAILED) {
+ DL_ERR("couldn't zero fill \"%s\" gap: %s", name_, strerror(errno));
+ return false;
+ }
+ }
+ }
+ return true;
}
/* Used internally. Used to set the protection bits of all loaded segments
@@ -550,7 +569,7 @@
phdr_table_get_dynamic_section(const Elf32_Phdr* phdr_table,
int phdr_count,
Elf32_Addr load_bias,
- Elf32_Addr** dynamic,
+ Elf32_Dyn** dynamic,
size_t* dynamic_count,
Elf32_Word* dynamic_flags)
{
@@ -562,7 +581,7 @@
continue;
}
- *dynamic = (Elf32_Addr*)(load_bias + phdr->p_vaddr);
+ *dynamic = reinterpret_cast<Elf32_Dyn*>(load_bias + phdr->p_vaddr);
if (dynamic_count) {
*dynamic_count = (unsigned)(phdr->p_memsz / 8);
}
@@ -577,72 +596,55 @@
}
}
-/* Return the address of the program header table as it appears in the loaded
- * segments in memory. This is in contrast with the input 'phdr_table' which
- * is temporary and will be released before the library is relocated.
- *
- * Input:
- * phdr_table -> program header table
- * phdr_count -> number of entries in tables
- * load_bias -> load bias
- * Return:
- * Address of loaded program header table on success (it has
- * 'phdr_count' entries), or NULL on failure (no error code).
- */
-const Elf32_Phdr*
-phdr_table_get_loaded_phdr(const Elf32_Phdr* phdr_table,
- int phdr_count,
- Elf32_Addr load_bias)
-{
- const Elf32_Phdr* phdr = phdr_table;
- const Elf32_Phdr* phdr_limit = phdr + phdr_count;
- Elf32_Addr loaded = 0;
- Elf32_Addr loaded_end;
+// Returns the address of the program header table as it appears in the loaded
+// segments in memory. This is in contrast with 'phdr_table_' which
+// is temporary and will be released before the library is relocated.
+bool ElfReader::FindPhdr() {
+ const Elf32_Phdr* phdr_limit = phdr_table_ + phdr_num_;
- /* If there is a PT_PHDR, use it directly */
- for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
- if (phdr->p_type == PT_PHDR) {
- loaded = load_bias + phdr->p_vaddr;
- goto CHECK;
- }
+ // If there is a PT_PHDR, use it directly.
+ for (const Elf32_Phdr* phdr = phdr_table_; phdr < phdr_limit; ++phdr) {
+ if (phdr->p_type == PT_PHDR) {
+ return CheckPhdr(load_bias_ + phdr->p_vaddr);
}
+ }
- /* Otherwise, check the first loadable segment. If its file offset
- * is 0, it starts with the ELF header, and we can trivially find the
- * loaded program header from it. */
- for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
- if (phdr->p_type == PT_LOAD) {
- if (phdr->p_offset == 0) {
- Elf32_Addr elf_addr = load_bias + phdr->p_vaddr;
- const Elf32_Ehdr* ehdr = (const Elf32_Ehdr*)(void*)elf_addr;
- Elf32_Addr offset = ehdr->e_phoff;
- loaded = (Elf32_Addr)ehdr + offset;
- goto CHECK;
- }
- break;
- }
+ // Otherwise, check the first loadable segment. If its file offset
+ // is 0, it starts with the ELF header, and we can trivially find the
+ // loaded program header from it.
+ for (const Elf32_Phdr* phdr = phdr_table_; phdr < phdr_limit; ++phdr) {
+ if (phdr->p_type == PT_LOAD) {
+ if (phdr->p_offset == 0) {
+ Elf32_Addr elf_addr = load_bias_ + phdr->p_vaddr;
+ const Elf32_Ehdr* ehdr = (const Elf32_Ehdr*)(void*)elf_addr;
+ Elf32_Addr offset = ehdr->e_phoff;
+ return CheckPhdr((Elf32_Addr)ehdr + offset);
+ }
+ break;
}
+ }
- /* We didn't find it, let the client know. He may be able to
- * keep a copy of the input phdr_table instead. */
- return NULL;
+ DL_ERR("can't find loaded phdr for \"%s\"", name_);
+ return false;
+}
-CHECK:
- /* Ensure that our program header is actually within a loadable
- * segment. This should help catch badly-formed ELF files that
- * would cause the linker to crash later when trying to access it.
- */
- loaded_end = loaded + phdr_count*sizeof(Elf32_Phdr);
-
- for (phdr = phdr_table; phdr < phdr_limit; phdr++) {
- if (phdr->p_type != PT_LOAD)
- continue;
- Elf32_Addr seg_start = phdr->p_vaddr + load_bias;
- Elf32_Addr seg_end = phdr->p_filesz + seg_start;
-
- if (seg_start <= loaded && loaded_end <= seg_end) {
- return (const Elf32_Phdr*)loaded;
- }
+// Ensures that our program header is actually within a loadable
+// segment. This should help catch badly-formed ELF files that
+// would cause the linker to crash later when trying to access it.
+bool ElfReader::CheckPhdr(Elf32_Addr loaded) {
+ const Elf32_Phdr* phdr_limit = phdr_table_ + phdr_num_;
+ Elf32_Addr loaded_end = loaded + (phdr_num_ * sizeof(Elf32_Phdr));
+ for (Elf32_Phdr* phdr = phdr_table_; phdr < phdr_limit; ++phdr) {
+ if (phdr->p_type != PT_LOAD) {
+ continue;
}
- return NULL;
+ Elf32_Addr seg_start = phdr->p_vaddr + load_bias_;
+ Elf32_Addr seg_end = phdr->p_filesz + seg_start;
+ if (seg_start <= loaded && loaded_end <= seg_end) {
+ loaded_phdr_ = reinterpret_cast<const Elf32_Phdr*>(loaded);
+ return true;
+ }
+ }
+ DL_ERR("\"%s\" loaded phdr %x not in loadable segment", name_, loaded);
+ return false;
}
diff --git a/linker/linker_phdr.h b/linker/linker_phdr.h
index d9a4820..a31d1d9 100644
--- a/linker/linker_phdr.h
+++ b/linker/linker_phdr.h
@@ -37,33 +37,50 @@
#include "linker.h"
-int
-phdr_table_load(int fd,
- Elf32_Addr phdr_offset,
- Elf32_Half phdr_num,
- void** phdr_mmap,
- Elf32_Addr* phdr_size,
- const Elf32_Phdr** phdr_table);
+class ElfReader {
+ public:
+ ElfReader(const char* name, int fd);
+ ~ElfReader();
-void
-phdr_table_unload(void* phdr_mmap, Elf32_Addr phdr_memsize);
+ bool Load();
-Elf32_Addr
-phdr_table_get_load_size(const Elf32_Phdr* phdr_table,
- size_t phdr_count);
+ size_t phdr_count() { return phdr_num_; }
+ Elf32_Addr load_start() { return reinterpret_cast<Elf32_Addr>(load_start_); }
+ Elf32_Addr load_size() { return load_size_; }
+ Elf32_Addr load_bias() { return load_bias_; }
+ const Elf32_Phdr* loaded_phdr() { return loaded_phdr_; }
-int
-phdr_table_reserve_memory(const Elf32_Phdr* phdr_table,
- size_t phdr_count,
- void** load_start,
- Elf32_Addr* load_size,
- Elf32_Addr* load_bias);
+ private:
+ bool ReadElfHeader();
+ bool VerifyElfHeader();
+ bool ReadProgramHeader();
+ bool ReserveAddressSpace();
+ bool LoadSegments();
+ bool FindPhdr();
+ bool CheckPhdr(Elf32_Addr);
-int
-phdr_table_load_segments(const Elf32_Phdr* phdr_table,
- int phdr_count,
- Elf32_Addr load_bias,
- int fd);
+ const char* name_;
+ int fd_;
+
+ Elf32_Ehdr header_;
+ size_t phdr_num_;
+
+ void* phdr_mmap_;
+ Elf32_Phdr* phdr_table_;
+ Elf32_Addr phdr_size_;
+
+ // First page of reserved address space.
+ void* load_start_;
+ // Size in bytes of reserved address space.
+ Elf32_Addr load_size_;
+ // Load bias.
+ Elf32_Addr load_bias_;
+
+ // Loaded phdr.
+ const Elf32_Phdr* loaded_phdr_;
+};
+
+Elf32_Addr phdr_table_get_load_size(const Elf32_Phdr* phdr, size_t phnum);
int
phdr_table_protect_segments(const Elf32_Phdr* phdr_table,
@@ -80,10 +97,6 @@
int phdr_count,
Elf32_Addr load_bias);
-const Elf32_Phdr*
-phdr_table_get_loaded_phdr(const Elf32_Phdr* phdr_table,
- int phdr_count,
- Elf32_Addr load_bias);
#ifdef ANDROID_ARM_LINKER
int
@@ -98,7 +111,7 @@
phdr_table_get_dynamic_section(const Elf32_Phdr* phdr_table,
int phdr_count,
Elf32_Addr load_bias,
- Elf32_Addr** dynamic,
+ Elf32_Dyn** dynamic,
size_t* dynamic_count,
Elf32_Word* dynamic_flags);