From 7865d19cf68bcfb32c12fa3e7ce6a85fb4738383 Mon Sep 17 00:00:00 2001 From: Viju Vincent Date: Wed, 15 Feb 2012 17:25:51 +0000 Subject: [PATCH] Resolve race between dlopen and lazy binding on MIPS. --- ChangeLog.mips | 5 +++++ sysdeps/mips/dl-trampoline.c | 30 +++++++++++++++++++++++++++++- 2 files changed, 34 insertions(+), 1 deletion(-) diff --git a/ChangeLog.mips b/ChangeLog.mips index ff8cfc2..2a9ed6c 100644 --- a/ChangeLog.mips +++ b/ChangeLog.mips @@ -1,3 +1,8 @@ +2012-02-15 Viju Vincent + + * sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Use locking + around calls to _dl_lookup_symbol_x. + 2012-02-13 Joseph Myers * sysdeps/unix/sysv/linux/mips/bits/inotify.h: New file. diff --git a/sysdeps/mips/dl-trampoline.c b/sysdeps/mips/dl-trampoline.c index 2c94140..c4367f7 100644 --- a/sysdeps/mips/dl-trampoline.c +++ b/sysdeps/mips/dl-trampoline.c @@ -26,6 +26,7 @@ #include #include #include +#include /* Get link map for callers object containing STUB_PC. */ static inline struct link_map * @@ -153,17 +154,44 @@ __dl_runtime_resolve (ElfW(Word) sym_index, if (version->hash != 0) { + /* We need to keep the scope around so do some locking. This is + not necessary for objects which cannot be unloaded or when + we are not using any threads (yet). */ + if (!RTLD_SINGLE_THREAD_P) + THREAD_GSCOPE_SET_FLAG (); + sym_map = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym, l->l_scope, version, ELF_RTYPE_CLASS_PLT, 0, 0); + + /* We are done with the global scope. */ + if (!RTLD_SINGLE_THREAD_P) + THREAD_GSCOPE_RESET_FLAG (); + break; } /* Fall through. */ } case 0: + { + /* We need to keep the scope around so do some locking. This is + not necessary for objects which cannot be unloaded or when + we are not using any threads (yet). */ + int flags = DL_LOOKUP_ADD_DEPENDENCY; + if (!RTLD_SINGLE_THREAD_P) + { + THREAD_GSCOPE_SET_FLAG (); + flags |= DL_LOOKUP_GSCOPE_LOCK; + } + sym_map = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym, l->l_scope, 0, ELF_RTYPE_CLASS_PLT, - DL_LOOKUP_ADD_DEPENDENCY, 0); + flags, 0); + + /* We are done with the global scope. */ + if (!RTLD_SINGLE_THREAD_P) + THREAD_GSCOPE_RESET_FLAG (); + } } /* Currently value contains the base load address of the object -- 2.7.4