Mercurial > gnulib
changeset 37246:5cfb3a67238d
regex: avoid glibc deadlock during configure
glibc has a known bug where certain corruptions of the heap can
cause malloc to default to printing a debug message that includes
a backtrace, but the act of getting the backtrace uses dlopen
which in turn calls into malloc, causing a recursive lock ending
in deadlock. Thus, when configure is probing for a known glibc
heap corruption bug, the overall configure would hang.
The solution suggested by glibc developers is to force malloc
to quit printing debug messages, which avoids recursive malloc.
* m4/regex.m4 (gl_REGEX): Avoid recursive malloc deadlock when
glibc bug 15078 in turn triggers bug 16159.
Reported by Michal Privoznik.
Signed-off-by: Eric Blake <eblake@redhat.com>
| author | Eric Blake <eblake@redhat.com> |
|---|---|
| date | Tue, 03 Dec 2013 10:34:13 -0700 |
| parents | 135e82dafbea |
| children | ef0f55e99386 |
| files | ChangeLog m4/regex.m4 |
| diffstat | 2 files changed, 19 insertions(+), 2 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog Sat Nov 30 05:19:32 2013 +0000 +++ b/ChangeLog Tue Dec 03 10:34:13 2013 -0700 @@ -1,3 +1,10 @@ +2013-12-03 Eric Blake <eblake@redhat.com> + + regex: avoid glibc deadlock during configure + * m4/regex.m4 (gl_REGEX): Avoid recursive malloc deadlock when + glibc bug 15078 in turn triggers bug 16159. + Reported by Michal Privoznik. + 2013-12-02 Pádraig Brady <P@draigBrady.com> md5, sha1, sha256, sha512: use openssl routines if available.
--- a/m4/regex.m4 Sat Nov 30 05:19:32 2013 +0000 +++ b/m4/regex.m4 Tue Dec 03 10:34:13 2013 -0700 @@ -1,4 +1,4 @@ -# serial 64 +# serial 65 # Copyright (C) 1996-2001, 2003-2013 Free Software Foundation, Inc. # @@ -28,6 +28,7 @@ # If cross compiling, assume the test would fail and use the included # regex.c. AC_CHECK_DECLS_ONCE([alarm]) + AC_CHECK_HEADERS_ONCE([malloc.h]) AC_CACHE_CHECK([for working re_compile_pattern], [gl_cv_func_re_compile_pattern_working], [AC_RUN_IFELSE( @@ -41,6 +42,9 @@ # include <unistd.h> # include <signal.h> #endif + #if HAVE_MALLOC_H + # include <malloc.h> + #endif ]], [[int result = 0; static struct re_pattern_buffer regex; @@ -49,11 +53,17 @@ const char *s; struct re_registers regs; + /* Some builds of glibc go into an infinite loop on this + test. Use alarm to force death, and mallopt to avoid + malloc recursion in diagnosing the corrupted heap. */ #if HAVE_DECL_ALARM - /* Some builds of glibc go into an infinite loop on this test. */ signal (SIGALRM, SIG_DFL); alarm (2); #endif +#ifdef M_CHECK_ACTION + mallopt(M_CHECK_ACTION, 2); +#endif + if (setlocale (LC_ALL, "en_US.UTF-8")) { {