lkml.org 
[lkml]   [2018]   [Jun]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH 3.16 246/410] binder: check for binder_thread allocation failure in binder_poll()
3.16.57-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Biggers <ebiggers@google.com>

commit f88982679f54f75daa5b8eff3da72508f1e7422f upstream.

If the kzalloc() in binder_get_thread() fails, binder_poll()
dereferences the resulting NULL pointer.

Fix it by returning POLLERR if the memory allocation failed.

This bug was found by syzkaller using fault injection.

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 457b9a6f09f0 ("Staging: android: add binder driver")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16:
- Drop the binder global lock before returning
- Adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -2572,6 +2572,10 @@ static unsigned int binder_poll(struct f
binder_lock(__func__);

thread = binder_get_thread(proc);
+ if (!thread) {
+ binder_unlock(__func__);
+ return POLLERR;
+ }

wait_for_proc_work = thread->transaction_stack == NULL &&
list_empty(&thread->todo) && thread->return_error == BR_OK;
\
 
 \ /
  Last update: 2018-06-07 17:18    [W:1.055 / U:0.280 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site