From 9221725d1f6e3f5dd0c0143ee750460619c582f2 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Tue, 23 Jun 2020 23:50:56 +0930 Subject: [PATCH] PR26150, Assertion when asm() defines global symbols, -flto and --start-group If an archive map contains symbols that aren't actually defined by the indexed element for any reason, then loading that element will leave the symbol undefined (or common). This leads to the possibility of the element being loaded again should the archive be searched again due to the action of --start-group/--end-group. The testcase triggering this problem was an archive containing fat lto objects, with the archive map incorrectly created by ar rather than gcc-ar. PR 26150 * ldlang.c (ldlang_add_file): Assert that we aren't adding the current end of link.next list again too. * ldmain.c (add_archive_element): Don't load archive elements again that have already been loaded. --- ld/ChangeLog | 8 ++++++++ ld/ldlang.c | 3 ++- ld/ldmain.c | 21 +++++++++++++++++---- 3 files changed, 27 insertions(+), 5 deletions(-) diff --git a/ld/ChangeLog b/ld/ChangeLog index d59b00b75da..a2e3f62e9e7 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,11 @@ +2020-06-23 Alan Modra + + PR 26150 + * ldlang.c (ldlang_add_file): Assert that we aren't adding the + current end of link.next list again too. + * ldmain.c (add_archive_element): Don't load archive elements + again that have already been loaded. + 2020-06-23 Alan Modra * testsuite/ld-elf/shared.exp (pr14170): Clear xfail for diff --git a/ld/ldlang.c b/ld/ldlang.c index 8ab6a0b0c36..38ed83a274b 100644 --- a/ld/ldlang.c +++ b/ld/ldlang.c @@ -7266,7 +7266,8 @@ ldlang_add_file (lang_input_statement_type *entry) /* The BFD linker needs to have a list of all input BFDs involved in a link. */ - ASSERT (entry->the_bfd->link.next == NULL); + ASSERT (link_info.input_bfds_tail != &entry->the_bfd->link.next + && entry->the_bfd->link.next == NULL); ASSERT (entry->the_bfd != link_info.output_bfd); *link_info.input_bfds_tail = entry->the_bfd; diff --git a/ld/ldmain.c b/ld/ldmain.c index d34d30ae337..94a745ec315 100644 --- a/ld/ldmain.c +++ b/ld/ldmain.c @@ -822,10 +822,6 @@ add_archive_element (struct bfd_link_info *info, input->local_sym_name = bfd_get_filename (abfd); input->the_bfd = abfd; - parent = bfd_usrdata (abfd->my_archive); - if (parent != NULL && !parent->flags.reload) - parent->next = input; - /* Save the original data for trace files/tries below, as plugins (if enabled) may possibly alter it to point to a replacement BFD, but we still want to output the original BFD filename. */ @@ -853,6 +849,23 @@ add_archive_element (struct bfd_link_info *info, } #endif /* BFD_SUPPORTS_PLUGINS */ + if (link_info.input_bfds_tail == &input->the_bfd->link.next + || input->the_bfd->link.next != NULL) + { + /* We have already loaded this element, and are attempting to + load it again. This can happen when the archive map doesn't + match actual symbols defined by the element. */ + free (input); + bfd_set_error (bfd_error_malformed_archive); + return FALSE; + } + + /* Set the file_chain pointer of archives to the last element loaded + from the archive. See ldlang.c:find_rescan_insertion. */ + parent = bfd_usrdata (abfd->my_archive); + if (parent != NULL && !parent->flags.reload) + parent->next = input; + ldlang_add_file (input); if (config.map_file != NULL)