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#include <gelf.h>
#include <sys/ptrace.h>
#include "proc.h"
#include "common.h"
GElf_Addr
arch_plt_sym_val(struct ltelf *lte, size_t ndx, GElf_Rela * rela) {
return rela->r_offset;
}
/* XXX Apparently PPC64 doesn't support PLT breakpoints. */
void *
sym2addr(Process *proc, struct library_symbol *sym) {
void *addr = sym->enter_addr;
long pt_ret;
debug(3, 0);
if (sym->plt_type != LS_TOPLT_POINT) {
return addr;
}
if (proc->pid == 0) {
return 0;
}
if (options.debug >= 3) {
xinfdump(proc->pid, (void *)(((long)addr-32)&0xfffffff0),
sizeof(void*)*8);
}
// On a PowerPC-64 system, a plt is three 64-bit words: the first is the
// 64-bit address of the routine. Before the PLT has been initialized,
// this will be 0x0. In fact, the symbol table won't have the plt's
// address even. Ater the PLT has been initialized, but before it has
// been resolved, the first word will be the address of the function in
// the dynamic linker that will reslove the PLT. After the PLT is
// resolved, this will will be the address of the routine whose symbol
// is in the symbol table.
// On a PowerPC-32 system, there are two types of PLTs: secure (new) and
// non-secure (old). For the secure case, the PLT is simply a pointer
// and we can treat it much as we do for the PowerPC-64 case. For the
// non-secure case, the PLT is executable code and we can put the
// break-point right in the PLT.
pt_ret = ptrace(PTRACE_PEEKTEXT, proc->pid, addr, 0);
#if SIZEOF_LONG == 8
if (proc->mask_32bit) {
// Assume big-endian.
addr = (void *)((pt_ret >> 32) & 0xffffffff);
} else {
addr = (void *)pt_ret;
}
#else
/* XXX Um, so where exactly are we dealing with the non-secure
PLT thing? */
addr = (void *)pt_ret;
#endif
return addr;
}
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