From 03c1e456b079929a8290aeb4aadb05c0df73bfd2 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Sun, 19 Apr 2015 01:06:33 -0700 Subject: Better fix for setenv (..., NULL, ...) * stdlib/setenv.c (__add_to_environ): Dump core quickly if setenv (..., NULL, ...) is called. This time, do it the right way, and pacify GCC with a pragma. --- ChangeLog | 6 ++++++ stdlib/setenv.c | 18 +++++++++++++++++- 2 files changed, 23 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 0b648bfb11..a1d49cb3ec 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2015-04-19 Paul Eggert + + * stdlib/setenv.c (__add_to_environ): + Dump core quickly if setenv (..., NULL, ...) is called. + This time, do it the right way, and pacify GCC with a pragma. + 2015-04-17 Roland McGrath * elf/dl-close.c (_dl_close_worker) [DL_NNS == 1]: Just assert that diff --git a/stdlib/setenv.c b/stdlib/setenv.c index b60c4f0151..184a8cdd07 100644 --- a/stdlib/setenv.c +++ b/stdlib/setenv.c @@ -19,6 +19,13 @@ # include #endif +/* Pacify GCC; see the commentary about VALLEN below. This is needed + at least through GCC 4.9.2. Pacify GCC for the entire file, as + there seems to be no way to pacify GCC selectively, only for the + place where it's needed. Do not use DIAG_IGNORE_NEEDS_COMMENT + here, as it's not defined yet. */ +#pragma GCC diagnostic ignored "-Wmaybe-uninitialized" + #include #if !_LIBC # if !defined errno && !defined HAVE_ERRNO_DECL @@ -114,8 +121,17 @@ __add_to_environ (name, value, combined, replace) { char **ep; size_t size; + + /* Compute lengths before locking, so that the critical section is + less of a performance bottleneck. VALLEN is needed only if + COMBINED is null (unfortunately GCC is not smart enough to deduce + this; see the #pragma at the start of this file). Testing + COMBINED instead of VALUE causes setenv (..., NULL, ...) to dump + core now instead of corrupting memory later. */ const size_t namelen = strlen (name); - const size_t vallen = value != NULL ? strlen (value) + 1 : 0; + size_t vallen; + if (combined == NULL) + vallen = strlen (value) + 1; LOCK; -- cgit 1.4.1