glibc/CVE-2021-33574-part2.patch

52 lines
1.9 KiB
Diff

https://sourceware.org/git/?p=glibc.git;a=commitdiff_plain;h=8c06748c51750333d1516a2d342ed2361186e908
From: Florian Weimer <fweimer@redhat.com>
Date: Tue, 1 Jun 2021 15:51:41 +0000 (+0200)
Subject: Fix use of __pthread_attr_copy in mq_notify (bug 27896)
X-Git-Url: https://sourceware.org/git/?p=glibc.git;a=commitdiff_plain;h=8c06748c51750333d1516a2d342ed2361186e908
Fix use of __pthread_attr_copy in mq_notify (bug 27896)
__pthread_attr_copy can fail and does not initialize the attribute
structure in that case.
If __pthread_attr_copy is never called and there is no allocated
attribute, pthread_attr_destroy should not be called, otherwise
there is a null pointer dereference in rt/tst-mqueue6.
Fixes commit 42d359350510506b87101cf77202fefcbfc790cb
("Use __pthread_attr_copy in mq_notify (bug 27896)").
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 217b6dc298156bdb0d6aea9ea93e7e394a5ff091)
---
diff --git a/sysdeps/unix/sysv/linux/mq_notify.c b/sysdeps/unix/sysv/linux/mq_notify.c
index f7ddfe5a6c..6f46d29d1d 100644
--- a/sysdeps/unix/sysv/linux/mq_notify.c
+++ b/sysdeps/unix/sysv/linux/mq_notify.c
@@ -258,7 +258,14 @@ mq_notify (mqd_t mqdes, const struct sigevent *notification)
if (data.attr == NULL)
return -1;
- __pthread_attr_copy (data.attr, notification->sigev_notify_attributes);
+ int ret = __pthread_attr_copy (data.attr,
+ notification->sigev_notify_attributes);
+ if (ret != 0)
+ {
+ free (data.attr);
+ __set_errno (ret);
+ return -1;
+ }
}
/* Construct the new request. */
@@ -271,7 +278,7 @@ mq_notify (mqd_t mqdes, const struct sigevent *notification)
int retval = INLINE_SYSCALL (mq_notify, 2, mqdes, &se);
/* If it failed, free the allocated memory. */
- if (__glibc_unlikely (retval != 0))
+ if (retval != 0 && data.attr != NULL)
{
pthread_attr_destroy (data.attr);
free (data.attr);