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Hi! LD_DEBUG=statistics someprog leads to segfaults with current glibc. The problem is that print_statistics doesn't check for NULL _ns_loaded namespaces and happily dereferences it. While looking into it, I have noticed the num_relative_relocations computation doesn't match what do-rel.h is actually doing, particularly on !ELF_MACHINE_REL_RELATIVE RELA architectures it is processing relative relocations even if l_addr == 0, but the library is not prelinked. 2004-11-13 Jakub Jelinek <jakub@redhat.com> * elf/rtld.c (print_statistics): Avoid segfaults if not all namespaces are used. Fix computation of num_relative_relocations on RELA architectures other than IA-64 and Alpha. --- libc/elf/rtld.c.jj 2004-11-09 12:26:41.000000000 +0100 +++ libc/elf/rtld.c 2004-11-13 18:56:32.574028935 +0100 @@ -2336,19 +2336,29 @@ print_statistics (hp_timing_t *rtld_tota unsigned long int num_relative_relocations = 0; for (Lmid_t ns = 0; ns < DL_NNS; ++ns) { + if (GL(dl_ns)[ns]._ns_loaded == NULL) + continue; + struct r_scope_elem *scope = &GL(dl_ns)[ns]._ns_loaded->l_searchlist; for (unsigned int i = 0; i < scope->r_nlist; i++) { struct link_map *l = scope->r_list [i]; - if (!l->l_addr) - continue; - - if (l->l_info[VERSYMIDX (DT_RELCOUNT)]) + if (l->l_addr != 0 && l->l_info[VERSYMIDX (DT_RELCOUNT)]) num_relative_relocations += l->l_info[VERSYMIDX (DT_RELCOUNT)]->d_un.d_val; - if (l->l_info[VERSYMIDX (DT_RELACOUNT)]) +#ifndef ELF_MACHINE_REL_RELATIVE + /* Relative relocations are processed on these architectures if + library is loaded to different address than p_vaddr or + if not prelinked. */ + if ((l->l_addr != 0 || !map->l_info[VALIDX(DT_GNU_PRELINKED)]) + && l->l_info[VERSYMIDX (DT_RELACOUNT)]) +#else + /* On e.g. IA-64 or Alpha, relative relocations are processed + only if library is loaded to different address than p_vaddr. */ + if (l->l_addr != 0 && l->l_info[VERSYMIDX (DT_RELACOUNT)]) +#endif num_relative_relocations += l->l_info[VERSYMIDX (DT_RELACOUNT)]->d_un.d_val; } Jakub
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