From cf76df0e1fe09b0d504ca650fdaa01df5bf9ab72 Mon Sep 17 00:00:00 2001
From: Rich Felker <dalias@aerifal.cx>
Date: Fri, 7 Oct 2022 21:36:25 -0400
Subject: fix missing synchronization of pthread TSD keys with MT-fork

commit 167390f05564e0a4d3fcb4329377fd7743267560 seems to have
overlooked the presence of a lock here, probably because it was one of
the exceptions not using LOCK() but a rwlock.

as such, it can't be added to the generic table of locks to take, so
add an explicit atfork function for the pthread keys table. the order
it is called does not particularly matter since nothing else in libc
but pthread_exit interacts with keys.
---
 src/process/fork.c | 3 +++
 1 file changed, 3 insertions(+)

(limited to 'src/process')

diff --git a/src/process/fork.c b/src/process/fork.c
index 80e804b1..56f19313 100644
--- a/src/process/fork.c
+++ b/src/process/fork.c
@@ -37,6 +37,7 @@ static void dummy(int x) { }
 weak_alias(dummy, __fork_handler);
 weak_alias(dummy, __malloc_atfork);
 weak_alias(dummy, __aio_atfork);
+weak_alias(dummy, __pthread_key_atfork);
 weak_alias(dummy, __ldso_atfork);
 
 static void dummy_0(void) { }
@@ -51,6 +52,7 @@ pid_t fork(void)
 	int need_locks = libc.need_locks > 0;
 	if (need_locks) {
 		__ldso_atfork(-1);
+		__pthread_key_atfork(-1);
 		__aio_atfork(-1);
 		__inhibit_ptc();
 		for (int i=0; i<sizeof atfork_locks/sizeof *atfork_locks; i++)
@@ -78,6 +80,7 @@ pid_t fork(void)
 				else **atfork_locks[i] = 0;
 		__release_ptc();
 		if (ret) __aio_atfork(0);
+		__pthread_key_atfork(!ret);
 		__ldso_atfork(!ret);
 	}
 	__restore_sigs(&set);
-- 
cgit v1.2.1