From: Rich Felker <dalias@aerifal.cx>
Date: Wed, 8 Feb 2012 01:31:27 +0000 (-0500)
Subject: protect against cancellation in dlopen
X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=commitdiff_plain;h=f2baf4d7b8be043b231ecf7fc611247196acd9f5

protect against cancellation in dlopen

i'm not sure that it's "correct" for dlopen to block cancellation
when calling constructors for libraries it loads, but it sure seems
like the right thing. in any case, dlopen itself needs cancellation
blocked.
---

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index eda0046e..6ff8850c 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -610,9 +610,11 @@ void *dlopen(const char *file, int mode)
 {
 	struct dso *volatile p, *orig_tail = tail, *next;
 	size_t i;
+	int cs;
 
 	if (!file) return head;
 
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
 	pthread_rwlock_wrlock(&lock);
 
 	if (setjmp(rtld_fail)) {
@@ -628,8 +630,8 @@ void *dlopen(const char *file, int mode)
 		}
 		tail = orig_tail;
 		tail->next = 0;
-		pthread_rwlock_unlock(&lock);
-		return 0;
+		p = 0;
+		goto end;
 	}
 
 	p = load_library(file);
@@ -658,6 +660,7 @@ void *dlopen(const char *file, int mode)
 	do_init_fini(tail);
 end:
 	pthread_rwlock_unlock(&lock);
+	pthread_setcancelstate(cs, 0);
 	return p;
 }