/*
* The main trick with this program is that initially, we ourselves are not
- * dynamicly linked. This means that we cannot access any global variables or
- * call any functions. No globals initially, since the Global Offset Table
+ * dynamically linked. This means that we cannot access any global variables
+ * or call any functions. No globals initially, since the Global Offset Table
* (GOT) is initialized by the linker assuming a virtual address of 0, and no
* function calls initially since the Procedure Linkage Table (PLT) is not yet
* initialized.
*
* Fortunately, the linker itself leaves a few clues lying around, and when the
* kernel starts the image, there are a few further clues. First of all, there
- * is Auxiliary Vector Table information sitting on which is provided to us by
- * the kernel, and which includes information about the load address that the
- * program interpreter was loaded at, the number of sections, the address the
- * application was loaded at and so forth. Here this information is stored in
- * the array auxvt. For details see linux/fs/binfmt_elf.c where it calls
- * NEW_AUX_ENT() a bunch of time....
+ * is Auxiliary Vector Table information sitting on the stack which is provided
+ * to us by the kernel, and which includes information about the address
+ * that the program interpreter was loaded at, the number of sections, the
+ * address the application was loaded at, and so forth. Here this information
+ * is stored in the array auxvt. For details see linux/fs/binfmt_elf.c where
+ * it calls NEW_AUX_ENT() a bunch of times....
*
* Next, we need to find the GOT. On most arches there is a register pointing
* to the GOT, but just in case (and for new ports) I've added some (slow) C
/* Pull in all the arch specific stuff */
#include "dl-startup.h"
+#ifdef __LDSO_PRELINK_SUPPORT__
+/* These defined magically in the linker script. */
+extern char _begin[] attribute_hidden;
+#endif
+
/* Static declarations */
static int (*_dl_elf_main) (int, char **, char **);
aux_dat += 2;
}
- /* locate the ELF header. We need this done as soon as possible
- * (esp since SEND_STDERR() needs this on some platforms... */
+ /*
+ * Locate the dynamic linker ELF header. We need this done as soon as
+ * possible (esp since SEND_STDERR() needs this on some platforms...
+ */
+
+#ifdef __LDSO_PRELINK_SUPPORT__
+ /*
+ * The `_begin' symbol created by the linker script points to ld.so ELF
+ * We use it if the kernel is not passing a valid address through the auxvt.
+ */
+
+ if (!auxvt[AT_BASE].a_un.a_val)
+ auxvt[AT_BASE].a_un.a_val = (Elf32_Addr) &_begin;
+ /* Note: if the dynamic linker itself is prelinked, the load_addr is 0 */
+ DL_INIT_LOADADDR_BOOT(load_addr, elf_machine_load_address());
+#else
if (!auxvt[AT_BASE].a_un.a_val)
auxvt[AT_BASE].a_un.a_val = elf_machine_load_address();
DL_INIT_LOADADDR_BOOT(load_addr, auxvt[AT_BASE].a_un.a_val);
+#endif
header = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val;
/* Check the ELF header to make sure everything looks ok. */
_dl_exit(0);
}
SEND_EARLY_STDERR_DEBUG("ELF header=");
- SEND_ADDRESS_STDERR_DEBUG(DL_LOADADDR_BASE(load_addr), 1);
+ SEND_ADDRESS_STDERR_DEBUG(DL_LOADADDR_BASE(header), 1);
/* Locate the global offset table. Since this code must be PIC
* we can take advantage of the magic offset register, if we
DL_BOOT_COMPUTE_GOT(got);
/* Now, finally, fix up the location of the dynamic stuff */
- DL_BOOT_COMPUTE_DYN(dpnt, got, load_addr);
+ DL_BOOT_COMPUTE_DYN(dpnt, got, (DL_LOADADDR_TYPE)header);
SEND_EARLY_STDERR_DEBUG("First Dynamic section entry=");
SEND_ADDRESS_STDERR_DEBUG(dpnt, 1);
PERFORM_BOOTSTRAP_GOT(tpnt);
#endif
-#if !defined(PERFORM_BOOTSTRAP_GOT) || defined(__avr32__)
+#if !defined(PERFORM_BOOTSTRAP_GOT) || defined(__avr32__) || defined(__mips__)
/* OK, now do the relocations. We do not do a lazy binding here, so
that once we are done, we have considerably more flexibility. */
if (!indx && relative_count) {
rel_size -= relative_count * sizeof(ELF_RELOC);
- elf_machine_relative(load_addr, rel_addr, relative_count);
+ if (load_addr
+#ifdef __LDSO_PRELINK_SUPPORT__
+ || !tpnt->dynamic_info[DT_GNU_PRELINKED_IDX]
+#endif
+ )
+ elf_machine_relative(load_addr, rel_addr, relative_count);
rel_addr += relative_count * sizeof(ELF_RELOC);
}
__rtld_stack_end = (void *)(argv - 1);
- _dl_get_ready_to_run(tpnt, load_addr, auxvt, envp, argv
- DL_GET_READY_TO_RUN_EXTRA_ARGS);
+ _dl_elf_main = (int (*)(int, char **, char **))
+ _dl_get_ready_to_run(tpnt, (DL_LOADADDR_TYPE) header, auxvt, envp, argv
+ DL_GET_READY_TO_RUN_EXTRA_ARGS);
/* Transfer control to the application. */
SEND_STDERR_DEBUG("transfering control to application @ ");
- _dl_elf_main = (int (*)(int, char **, char **)) auxvt[AT_ENTRY].a_un.a_val;
SEND_ADDRESS_STDERR_DEBUG(_dl_elf_main, 1);
#if !defined(START)
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