This is a note to let you know that I've just added the patch titled
binder: fix memory leak in error path
to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-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 char-misc-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 1909a671dbc3606685b1daf8b22a16f65ea7edda Mon Sep 17 00:00:00 2001
From: Todd Kjos <tkjos@xxxxxxxxxxx>
Date: Fri, 21 Jun 2019 10:54:15 -0700
Subject: binder: fix memory leak in error path
syzkallar found a 32-byte memory leak in a rarely executed error
case. The transaction complete work item was not freed if put_user()
failed when writing the BR_TRANSACTION_COMPLETE to the user command
buffer. Fixed by freeing it before put_user() is called.
Reported-by: syzbot+182ce46596c3f2e1eb24@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Todd Kjos <tkjos@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/android/binder.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 748ac489ef7e..8b108e9b31cc 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -4256,6 +4256,8 @@ static int binder_thread_read(struct binder_proc *proc,
case BINDER_WORK_TRANSACTION_COMPLETE: {
binder_inner_proc_unlock(proc);
cmd = BR_TRANSACTION_COMPLETE;
+ kfree(w);
+ binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
if (put_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
@@ -4264,8 +4266,6 @@ static int binder_thread_read(struct binder_proc *proc,
binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
"%d:%d BR_TRANSACTION_COMPLETE\n",
proc->pid, thread->pid);
- kfree(w);
- binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
} break;
case BINDER_WORK_NODE: {
struct binder_node *node = container_of(w, struct binder_node, work);
--
2.22.0
