From 6b1e7d1992cd89032df431c0e0d1418b97e57cd8 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Mon, 30 May 2011 12:31:25 -0400 Subject: [PATCH] Handle DSOs without any dependency in ld.so --- ChangeLog | 6 ++++ NEWS | 4 +-- elf/dl-deps.c | 93 ++++++++++++++++++++++++++++++----------------------------- elf/dl-fini.c | 10 ++++--- elf/rtld.c | 1 - 5 files changed, 62 insertions(+), 52 deletions(-) diff --git a/ChangeLog b/ChangeLog index f5309df..31719ab 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,11 @@ 2011-05-30 Ulrich Drepper + [BZ #12454] + * elf/dl-deps.c (_dl_map_object_deps): Run initializer sorting only + when there are multiple maps. + * elf/dl-fini.c (_dl_sort_fini): Check for list of one. + (_dl_fini): Remove test here. + * elf/rtld.c (dl_main): Don't allow the loader to load itself. 2011-05-29 Ulrich Drepper diff --git a/NEWS b/NEWS index 05f603f..b3d8005 100644 --- a/NEWS +++ b/NEWS @@ -1,4 +1,4 @@ -GNU C Library NEWS -- history of user-visible changes. 2011-5-29 +GNU C Library NEWS -- history of user-visible changes. 2011-5-30 Copyright (C) 1992-2009, 2010, 2011 Free Software Foundation, Inc. See the end for copying conditions. @@ -23,7 +23,7 @@ Version 2.14 * The RPC implementation in libc is obsoleted. Old programs keep working but new programs cannot be linked with the routines in libc anymore. Programs in need of RPC functionality must be linked against TI-RPC. - The TI-RPC implemtation is IPv6 enabled and there are other benefits. + The TI-RPC implementation is IPv6 enabled and there are other benefits. Visible changes of this change include (obviously) the inability to link programs using RPC functions without referencing the TI-RPC library and the diff --git a/elf/dl-deps.c b/elf/dl-deps.c index d3c27f1..0b03b90 100644 --- a/elf/dl-deps.c +++ b/elf/dl-deps.c @@ -617,61 +617,64 @@ Filters not supported with LD_TRACE_PRELINKING")); map->l_searchlist.r_list[i]->l_reserved = 0; } - /* Now determine the order in which the initialization has to happen. */ + /* Sort the initializer list to take dependencies into account. The binary + itself will always be initialize last. */ memcpy (l_initfini, map->l_searchlist.r_list, nlist * sizeof (struct link_map *)); - - /* We can skip looking for the binary itself which is at the front - of the search list. */ - assert (nlist > 1); - i = 1; - bool seen[nlist]; - memset (seen, false, nlist * sizeof (seen[0])); - while (1) + if (__builtin_expect (nlist > 1, 1)) { - /* Keep track of which object we looked at this round. */ - seen[i] = true; - struct link_map *thisp = l_initfini[i]; - - /* Find the last object in the list for which the current one is - a dependency and move the current object behind the object - with the dependency. */ - unsigned int k = nlist - 1; - while (k > i) + /* We can skip looking for the binary itself which is at the front + of the search list. */ + i = 1; + bool seen[nlist]; + memset (seen, false, nlist * sizeof (seen[0])); + while (1) { - struct link_map **runp = l_initfini[k]->l_initfini; - if (runp != NULL) - /* Look through the dependencies of the object. */ - while (*runp != NULL) - if (__builtin_expect (*runp++ == thisp, 0)) - { - /* Move the current object to the back past the last - object with it as the dependency. */ - memmove (&l_initfini[i], &l_initfini[i + 1], - (k - i) * sizeof (l_initfini[0])); - l_initfini[k] = thisp; - - if (seen[i + 1]) + /* Keep track of which object we looked at this round. */ + seen[i] = true; + struct link_map *thisp = l_initfini[i]; + + /* Find the last object in the list for which the current one is + a dependency and move the current object behind the object + with the dependency. */ + unsigned int k = nlist - 1; + while (k > i) + { + struct link_map **runp = l_initfini[k]->l_initfini; + if (runp != NULL) + /* Look through the dependencies of the object. */ + while (*runp != NULL) + if (__builtin_expect (*runp++ == thisp, 0)) { - ++i; - goto next_clear; + /* Move the current object to the back past the last + object with it as the dependency. */ + memmove (&l_initfini[i], &l_initfini[i + 1], + (k - i) * sizeof (l_initfini[0])); + l_initfini[k] = thisp; + + if (seen[i + 1]) + { + ++i; + goto next_clear; + } + + memmove (&seen[i], &seen[i + 1], + (k - i) * sizeof (seen[0])); + seen[k] = true; + + goto next; } - memmove (&seen[i], &seen[i + 1], (k - i) * sizeof (seen[0])); - seen[k] = true; + --k; + } - goto next; - } + if (++i == nlist) + break; + next_clear: + memset (&seen[i], false, (nlist - i) * sizeof (seen[0])); - --k; + next:; } - - if (++i == nlist) - break; - next_clear: - memset (&seen[i], false, (nlist - i) * sizeof (seen[0])); - - next:; } /* Terminate the list of dependencies. */ diff --git a/elf/dl-fini.c b/elf/dl-fini.c index ba6c62a..269bcec 100644 --- a/elf/dl-fini.c +++ b/elf/dl-fini.c @@ -33,9 +33,12 @@ internal_function _dl_sort_fini (struct link_map *l, struct link_map **maps, size_t nmaps, char *used, Lmid_t ns) { + /* A list of one element need not be sorted. */ + if (nmaps == 1) + return; + /* We can skip looking for the binary itself which is at the front of the search list for the main namespace. */ - assert (nmaps > 1); unsigned int i = ns == LM_ID_BASE; bool seen[nmaps]; memset (seen, false, nmaps * sizeof (seen[0])); @@ -195,9 +198,8 @@ _dl_fini (void) assert (ns == LM_ID_BASE || i == nloaded || i == nloaded - 1); nmaps = i; - if (nmaps > 1) - /* Now we have to do the sorting. */ - _dl_sort_fini (GL(dl_ns)[ns]._ns_loaded, maps, nmaps, NULL, ns); + /* Now we have to do the sorting. */ + _dl_sort_fini (GL(dl_ns)[ns]._ns_loaded, maps, nmaps, NULL, ns); /* We do not rely on the linked list of loaded object anymore from this point on. We have our own list here (maps). The various diff --git a/elf/rtld.c b/elf/rtld.c index 48c5574..9eb9289 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -922,7 +922,6 @@ dl_main (const ElfW(Phdr) *phdr, /* Process the environment variable which control the behaviour. */ process_envvars (&mode); - mode=trace; #ifndef HAVE_INLINED_SYSCALLS /* Set up a flag which tells we are just starting. */ -- 2.7.4