patch "staging: android: sync: Fix memory corruption in" added to staging-testing

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    staging: android: sync: Fix memory corruption in

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-testing branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will be merged to the staging-next branch sometime soon,
after it passes testing, and the merge window is open.

If you have any questions about this process, please let me know.


>From 8e43c9c75faf2902955bd2ecd7a50a8cc41cb00a Mon Sep 17 00:00:00 2001
From: Alistair Strachan <alistair.strachan@xxxxxxxxxx>
Date: Tue, 24 Mar 2015 14:51:31 -0700
Subject: staging: android: sync: Fix memory corruption in
 sync_timeline_signal().

The android_fence_release() function checks for active sync points
by calling list_empty() on the list head embedded on the sync
point. However, it is only valid to use list_empty() on nodes that
have been initialized with INIT_LIST_HEAD() or list_del_init().

Because the list entry has likely been removed from the active list
by sync_timeline_signal(), there is a good chance that this
WARN_ON_ONCE() will be hit due to dangling pointers pointing at
freed memory (even though the sync drivers did nothing wrong)
and memory corruption will ensue as the list entry is removed for
a second time, corrupting the active list.

This problem can be reproduced quite easily with CONFIG_DEBUG_LIST=y
and fences with more than one sync point.

Signed-off-by: Alistair Strachan <alistair.strachan@xxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Colin Cross <ccross@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/staging/android/sync.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c
index 7bdb62bf6b40..f83e00c78051 100644
--- a/drivers/staging/android/sync.c
+++ b/drivers/staging/android/sync.c
@@ -114,7 +114,7 @@ void sync_timeline_signal(struct sync_timeline *obj)
 	list_for_each_entry_safe(pt, next, &obj->active_list_head,
 				 active_list) {
 		if (fence_is_signaled_locked(&pt->base))
-			list_del(&pt->active_list);
+			list_del_init(&pt->active_list);
 	}
 
 	spin_unlock_irqrestore(&obj->child_list_lock, flags);
-- 
2.3.4


--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]