dns: treat names rejected by res_mkquery as nonexistent rather than error

[musl] / ldso / dynlink.c

diff --git a/ldso/dynlink.c b/ldso/dynlink.c
index 8b67ef5..03f5fd5 100644 (file)
--- a/ldso/dynlink.c
+++ b/ldso/dynlink.c
@@ -29,7 +29,9 @@
 #define realloc __libc_realloc
 #define free __libc_free
 
-static void error(const char *, ...);
+static void error_impl(const char *, ...);
+static void error_noop(const char *, ...);
+static void (*error)(const char *, ...) = error_noop;
 
 #define MAXP2(a,b) (-(-(a)&-(b)))
 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
@@ -208,7 +210,8 @@ static void decode_vec(size_t *v, size_t *a, size_t cnt)
        size_t i;
        for (i=0; i<cnt; i++) a[i] = 0;
        for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
-               a[0] |= 1UL<<v[0];
+               if (v[0] < 8*sizeof(long))
+                       a[0] |= 1UL<<v[0];
                a[v[0]] = v[1];
        }
 }
@@ -513,6 +516,23 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri
        }
 }
 
+static void do_relr_relocs(struct dso *dso, size_t *relr, size_t relr_size)
+{
+       unsigned char *base = dso->base;
+       size_t *reloc_addr;
+       for (; relr_size; relr++, relr_size-=sizeof(size_t))
+               if ((relr[0]&1) == 0) {
+                       reloc_addr = laddr(dso, relr[0]);
+                       *reloc_addr++ += (size_t)base;
+               } else {
+                       int i = 0;
+                       for (size_t bitmap=relr[0]; (bitmap>>=1); i++)
+                               if (bitmap&1)
+                                       reloc_addr[i] += (size_t)base;
+                       reloc_addr += 8*sizeof(size_t)-1;
+               }
+}
+
 static void redo_lazy_relocs()
 {
        struct dso *p = lazy_head, *next;
@@ -866,7 +886,7 @@ static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
                case ENOENT:
                case ENOTDIR:
                case EACCES:
-                       break;
+                       return 0;
                default:
                        return -1;
                }
@@ -1355,13 +1375,17 @@ static void reloc_all(struct dso *p)
                        2+(dyn[DT_PLTREL]==DT_RELA));
                do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);
                do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);
-
-               if (head != &ldso && p->relro_start != p->relro_end &&
-                   mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_start, PROT_READ)
-                   && errno != ENOSYS) {
-                       error("Error relocating %s: RELRO protection failed: %m",
-                               p->name);
-                       if (runtime) longjmp(*rtld_fail, 1);
+               if (!DL_FDPIC)
+                       do_relr_relocs(p, laddr(p, dyn[DT_RELR]), dyn[DT_RELRSZ]);
+
+               if (head != &ldso && p->relro_start != p->relro_end) {
+                       long ret = __syscall(SYS_mprotect, laddr(p, p->relro_start),
+                               p->relro_end-p->relro_start, PROT_READ);
+                       if (ret != 0 && ret != -ENOSYS) {
+                               error("Error relocating %s: RELRO protection failed: %m",
+                                       p->name);
+                               if (runtime) longjmp(*rtld_fail, 1);
+                       }
                }
 
                p->relocated = 1;
@@ -1756,6 +1780,9 @@ void __dls3(size_t *sp, size_t *auxv)
                env_preload = getenv("LD_PRELOAD");
        }
 
+       /* Activate error handler function */
+       error = error_impl;
+
        /* If the main program was already loaded by the kernel,
         * AT_PHDR will point to some location other than the dynamic
         * linker's program headers. */
@@ -1831,7 +1858,7 @@ void __dls3(size_t *sp, size_t *auxv)
                        dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
                        _exit(1);
                }
-               Ehdr *ehdr = (void *)map_library(fd, &app);
+               Ehdr *ehdr = map_library(fd, &app);
                if (!ehdr) {
                        dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
                        _exit(1);
@@ -2345,7 +2372,7 @@ int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void
        return ret;
 }
 
-static void error(const char *fmt, ...)
+static void error_impl(const char *fmt, ...)
 {
        va_list ap;
        va_start(ap, fmt);
@@ -2359,3 +2386,7 @@ static void error(const char *fmt, ...)
        __dl_vseterr(fmt, ap);
        va_end(ap);
 }
+
+static void error_noop(const char *fmt, ...)
+{
+}