From e829695fcc880f8578c2b964ea2d090f0016c9d7 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Wed, 27 Jun 2018 15:29:12 -0400 Subject: [PATCH] avoid using undefined pointer arithmetic in dladdr --- ldso/dynlink.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/ldso/dynlink.c b/ldso/dynlink.c index eecbddb5..6b05b5e0 100644 --- a/ldso/dynlink.c +++ b/ldso/dynlink.c @@ -1943,16 +1943,17 @@ failed: return 0; } -int dladdr(const void *addr, Dl_info *info) +int dladdr(const void *addr_arg, Dl_info *info) { + size_t addr = (size_t)addr_arg; struct dso *p; Sym *sym, *bestsym; uint32_t nsym; char *strings; - void *best = 0; + size_t best = 0; pthread_rwlock_rdlock(&lock); - p = addr2dso((size_t)addr); + p = addr2dso(addr); pthread_rwlock_unlock(&lock); if (!p) return 0; @@ -1962,10 +1963,10 @@ int dladdr(const void *addr, Dl_info *info) nsym = count_syms(p); if (DL_FDPIC) { - size_t idx = ((size_t)addr-(size_t)p->funcdescs) + size_t idx = (addr-(size_t)p->funcdescs) / sizeof(*p->funcdescs); if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) { - best = p->funcdescs + idx; + best = (size_t)(p->funcdescs + idx); bestsym = sym + idx; } } @@ -1974,7 +1975,7 @@ int dladdr(const void *addr, Dl_info *info) if (sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES) && (1<<(sym->st_info>>4) & OK_BINDS)) { - void *symaddr = laddr(p, sym->st_value); + size_t symaddr = (size_t)laddr(p, sym->st_value); if (symaddr > addr || symaddr < best) continue; best = symaddr; @@ -1987,12 +1988,12 @@ int dladdr(const void *addr, Dl_info *info) if (!best) return 0; if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC) - best = p->funcdescs + (bestsym - p->syms); + best = (size_t)(p->funcdescs + (bestsym - p->syms)); info->dli_fname = p->name; info->dli_fbase = p->map; info->dli_sname = strings + bestsym->st_name; - info->dli_saddr = best; + info->dli_saddr = (void *)best; return 1; } -- 2.25.1