From: Todd Kjos Date: Fri, 21 Jun 2019 17:54:15 +0000 (-0700) Subject: binder: fix memory leak in error path X-Git-Tag: v5.3-rc1~127^2~36 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=1909a671dbc3606685b1daf8b22a16f65ea7edda;p=linux.git 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 Cc: stable Signed-off-by: Greg Kroah-Hartman --- 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);