From: Martijn Coenen Date: Wed, 28 Mar 2018 09:14:50 +0000 (+0200) Subject: ANDROID: binder: prevent transactions into own process. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fd0485e2cc7b5f69889dca223b2c9f7cba6e91f4;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git ANDROID: binder: prevent transactions into own process. commit 7aa135fcf26377f92dc0680a57566b4c7f3e281b upstream. This can't happen with normal nodes (because you can't get a ref to a node you own), but it could happen with the context manager; to make the behavior consistent with regular nodes, reject transactions into the context manager by the process owning it. Reported-by: syzbot+09e05aba06723a94d43d@syzkaller.appspotmail.com Signed-off-by: Martijn Coenen Cc: stable Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/android/binder.c b/drivers/android/binder.c index b7efdc8badee..a86c27948fca 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2785,6 +2785,14 @@ static void binder_transaction(struct binder_proc *proc, else return_error = BR_DEAD_REPLY; mutex_unlock(&context->context_mgr_node_lock); + if (target_node && target_proc == proc) { + binder_user_error("%d:%d got transaction to context manager from process owning it\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_invalid_target_handle; + } } if (!target_node) { /*