From 6b3d5e508fcf16abe18c163c4c31a47f2d35a306 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sun, 26 Jun 2011 17:39:17 -0400 Subject: error handling in dynamic linking some of the code is not yet used, and is in preparation for dlopen which needs to be able to handle failure loading libraries without terminating the program. --- src/ldso/dynlink.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c index 9e9415ca..03f09208 100644 --- a/src/ldso/dynlink.c +++ b/src/ldso/dynlink.c @@ -12,6 +12,7 @@ #include #include #include +#include #include "reloc.h" @@ -44,11 +45,14 @@ struct dso ino_t ino; int global; int relocated; - char name[]; + char *name; + char buf[]; }; static struct dso *head, *tail, *libc; static char *env_path, *sys_path; +static int runtime; +static jmp_buf rtld_fail; #define AUX_CNT 15 #define DYN_CNT 34 @@ -115,6 +119,11 @@ static void do_relocs(unsigned char *base, size_t *rel, size_t rel_size, size_t name = strings + sym->st_name; ctx = IS_COPY(type) ? dso->next : dso; sym_val = (size_t)find_sym(ctx, name, IS_PLT(type)); + if (!sym_val && sym->st_info>>4 != STB_WEAK) { + if (runtime) longjmp(rtld_fail, 1); + dprintf(2, "%s: symbol not found\n", name); + _exit(127); + } sym_size = sym->st_size; } do_single_reloc(reloc_addr, type, sym_val, sym_size, base, rel[2]); @@ -308,6 +317,7 @@ static struct dso *load_library(const char *name) p->ino = st.st_ino; p->global = 1; p->refcnt = 1; + p->name = p->buf; strcpy(p->name, name); tail->next = p; @@ -323,7 +333,12 @@ static void load_deps(struct dso *p) for (; p; p=p->next) { for (i=0; p->dynv[i]; i+=2) { if (p->dynv[i] != DT_NEEDED) continue; - load_library(p->strings + p->dynv[i+1]); + if (!load_library(p->strings + p->dynv[i+1])) { + if (runtime) longjmp(rtld_fail, 1); + dprintf(2, "%s: %m (needed by %s)\n", + p->strings + p->dynv[i+1], p->name); + _exit(127); + } } } } @@ -395,6 +410,7 @@ void *__dynlink(int argc, char **argv, size_t *got) .hashtab = (void *)(app_dyn[DT_HASH]), .syms = (void *)(app_dyn[DT_SYMTAB]), .dynv = (void *)(phdr->p_vaddr), + .name = argv[0], .next = &lib }; @@ -404,6 +420,7 @@ void *__dynlink(int argc, char **argv, size_t *got) .hashtab = (void *)(aux[AT_BASE]+lib_dyn[DT_HASH]), .syms = (void *)(aux[AT_BASE]+lib_dyn[DT_SYMTAB]), .dynv = (void *)(got[0]), + .name = "libc.so", .relocated = 1 }; -- cgit v1.2.3-70-g09d2