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@android.com 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@syzkaller.appspotmail.com Signed-off-by: Todd Kjos tkjos@google.com Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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);