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| author | Ulrich Drepper <drepper@redhat.com> | 2007-06-09 19:45:57 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2007-06-09 19:45:57 +0000 |
| commit | 90cd2413df749eff9d055ef1868b616a65cf3fef (patch) | |
| tree | a6029c8c37fdd4e053ab5ac6bab748faa1b7f893 | |
| parent | 3c457089679373802fae6ef65a1804e1c9074b67 (diff) | |
| download | glibc-90cd2413df749eff9d055ef1868b616a65cf3fef.zip glibc-90cd2413df749eff9d055ef1868b616a65cf3fef.tar.gz glibc-90cd2413df749eff9d055ef1868b616a65cf3fef.tar.bz2 | |
* elf/do-lookup.h (do_lookup_x): Read r_nlist before r_list and
make sure gcc doesn't mess around with this.
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | elf/do-lookup.h | 9 |
2 files changed, 12 insertions, 2 deletions
@@ -1,3 +1,8 @@ +2007-06-09 Ulrich Drepper <drepper@redhat.com> + + * elf/do-lookup.h (do_lookup_x): Read r_nlist before r_list and + make sure gcc doesn't mess around with this. + 2007-06-08 Ulrich Drepper <drepper@redhat.com> * elf/dl-lookup.c (_dl_lookup_symbol_x): Remove use of r_nlist. diff --git a/elf/do-lookup.h b/elf/do-lookup.h index 2585d83..ab9a510 100644 --- a/elf/do-lookup.h +++ b/elf/do-lookup.h @@ -1,5 +1,5 @@ /* Look up a symbol in the loaded objects. - Copyright (C) 1995-2004, 2005, 2006 Free Software Foundation, Inc. + Copyright (C) 1995-2004, 2005, 2006, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -29,8 +29,13 @@ do_lookup_x (const char *undef_name, uint_fast32_t new_hash, const struct r_found_version *const version, int flags, struct link_map *skip, int type_class) { - struct link_map **list = scope->r_list; size_t n = scope->r_nlist; + /* Make sure we read the value before proceeding. Otherwise we + might use r_list pointing to the initial scope and r_nlist being + the value after a resize. That is the only path in dl-open.c not + protected by GSCOPE. A read barrier here might be to expensive. */ + __asm volatile ("" : "+r" (n), "+m" (scope->r_list)); + struct link_map **list = scope->r_list; do { |