main/libc0.9.32: fix malloc for child process after fork

1 files changed, 54 insertions, 0 deletions

diff --git a/main/libc0.9.32/0001-malloc-standard-synchronize-on-fork.patch b/main/libc0.9.32/0001-malloc-standard-synchronize-on-fork.patch
new file mode 100644
index 0000000000..eb3bfbe04f
--- /dev/null
+++ b/main/libc0.9.32/0001-malloc-standard-synchronize-on-fork.patch
@@ -0,0 +1,54 @@
+From 168215f9c3ec4ec9a2fad9387038ced8b386ebaa Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
+Date: Sat, 26 Mar 2011 20:23:09 +0200
+Subject: [PATCH] malloc-standard: synchronize on fork
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Otherwise other threads can leave malloc state locked, and the child
+will hang indefinitely if it tries to malloc something.
+
+Signed-off-by: Timo Teräs <timo.teras@iki.fi>
+---
+ libc/stdlib/malloc-standard/free.c |   17 +++++++++++++++++
+ 1 files changed, 17 insertions(+), 0 deletions(-)
+
+diff --git a/libc/stdlib/malloc-standard/free.c b/libc/stdlib/malloc-standard/free.c
+index 39e54d6..df512cc 100644
+--- a/libc/stdlib/malloc-standard/free.c
++++ b/libc/stdlib/malloc-standard/free.c
+@@ -118,6 +118,21 @@ int malloc_trim(size_t pad)
+   to inline it at all call points, which turns out not to be an
+   optimization at all. (Inlining it in __malloc_consolidate is fine though.)
+ */
++static void _malloc_lock(void)
++{
++    __UCLIBC_MUTEX_LOCK_CANCEL_UNSAFE(__malloc_lock);
++}
++
++static void _malloc_unlock(void)
++{
++    __UCLIBC_MUTEX_UNLOCK_CANCEL_UNSAFE(__malloc_lock);
++}
++
++static void _malloc_reset(void)
++{
++    __UCLIBC_MUTEX_INIT_VAR(__malloc_lock);
++}
++
+ static void malloc_init_state(mstate av)
+ {
+     int     i;
+@@ -145,6 +160,8 @@ static void malloc_init_state(mstate av)
+ 
+     av->top            = initial_top(av);
+     av->pagesize       = malloc_getpagesize;
++
++    __libc_atfork(_malloc_lock, _malloc_unlock, _malloc_reset);
+ }
+ 
+ 
+-- 
+1.7.1
+