diff options
Diffstat (limited to 'libc/bionic/libc_init_static.c')
-rw-r--r-- | libc/bionic/libc_init_static.c | 34 |
1 files changed, 6 insertions, 28 deletions
diff --git a/libc/bionic/libc_init_static.c b/libc/bionic/libc_init_static.c index ba7f008e9..bb3a41021 100644 --- a/libc/bionic/libc_init_static.c +++ b/libc/bionic/libc_init_static.c @@ -49,6 +49,7 @@ #include <bionic_tls.h> #include <errno.h> #include <sys/mman.h> +#include <sys/auxv.h> // Returns the address of the page containing address 'x'. #define PAGE_START(x) ((x) & PAGE_MASK) @@ -65,27 +66,13 @@ static void call_array(void(**list)()) } } -/* - * Find the value of the AT_* variable passed to us by the kernel. - */ -static unsigned find_aux(unsigned *vecs, unsigned type) { - while (vecs[0]) { - if (vecs[0] == type) { - return vecs[1]; - } - vecs += 2; - } - - return 0; // should never happen -} - -static void apply_gnu_relro(unsigned *vecs) { +static void apply_gnu_relro() { Elf32_Phdr *phdr_start; - unsigned phdr_ct; + unsigned long int phdr_ct; Elf32_Phdr *phdr; - phdr_start = (Elf32_Phdr *) find_aux(vecs, AT_PHDR); - phdr_ct = find_aux(vecs, AT_PHNUM); + phdr_start = (Elf32_Phdr *) getauxval(AT_PHDR); + phdr_ct = getauxval(AT_PHNUM); for (phdr = phdr_start; phdr < (phdr_start + phdr_ct); phdr++) { if (phdr->p_type != PT_GNU_RELRO) @@ -108,7 +95,6 @@ __noreturn void __libc_init(uintptr_t *elfdata, { int argc; char **argv, **envp; - unsigned *vecs; __libc_init_tls(NULL); @@ -129,14 +115,6 @@ __noreturn void __libc_init(uintptr_t *elfdata, argv = (char**)(elfdata + 1); envp = argv + argc + 1; - // The auxiliary vector is at the end of the environment block - vecs = (unsigned *) envp; - while (vecs[0] != 0) { - vecs++; - } - /* The end of the environment block is marked by two NULL pointers */ - vecs++; - /* The executable may have its own destructors listed in its .fini_array * so we need to ensure that these are called when the program exits * normally. @@ -144,6 +122,6 @@ __noreturn void __libc_init(uintptr_t *elfdata, if (structors->fini_array) __cxa_atexit(__libc_fini,structors->fini_array,NULL); - apply_gnu_relro(vecs); + apply_gnu_relro(); exit(slingshot(argc, argv, envp)); } |