[PATCH 2/4] binder: migrate ioctl to new PF_SPAM_DETECTION

From: Carlos Llamas <cmllamas@google.com>
To: "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
	"Arve Hjønnevåg" <arve@android.com>,
	"Todd Kjos" <tkjos@android.com>,
	"Martijn Coenen" <maco@android.com>,
	"Joel Fernandes" <joel@joelfernandes.org>,
	"Christian Brauner" <brauner@kernel.org>,
	"Carlos Llamas" <cmllamas@google.com>,
	"Suren Baghdasaryan" <surenb@google.com>,
	"Alice Ryhl" <aliceryhl@google.com>
Cc: linux-kernel@vger.kernel.org, kernel-team@android.com
Subject: [PATCH 2/4] binder: migrate ioctl to new PF_SPAM_DETECTION
Date: Wed, 17 Apr 2024 19:13:42 +0000	[thread overview]
Message-ID: <20240417191418.1341988-3-cmllamas@google.com> (raw)
In-Reply-To: <20240417191418.1341988-1-cmllamas@google.com>

Deprecate the BINDER_ENABLE_ONEWAY_SPAM_DETECTION ioctl in favor of the
new PF_SPAM_DETECTION flag. The ioctl can be lumped together with other
flags to avoid a separate system call. The driver still supports the old
ioctl for backwards compatibility.

Suggested-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Carlos Llamas <cmllamas@google.com>
---
 drivers/android/binder.c            | 7 ++++---
 drivers/android/binder_internal.h   | 1 -
 include/uapi/linux/android/binder.h | 8 ++++++--
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index e0d193bfb237..54d27dbf1de2 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -4486,8 +4486,8 @@ static int binder_thread_read(struct binder_proc *proc,
 		case BINDER_WORK_TRANSACTION_COMPLETE:
 		case BINDER_WORK_TRANSACTION_PENDING:
 		case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: {
-			if (proc->oneway_spam_detection_enabled &&
-				   w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
+			if (proc->flags & PF_SPAM_DETECTION &&
+			    w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
 				cmd = BR_ONEWAY_SPAM_SUSPECT;
 			else if (w->type == BINDER_WORK_TRANSACTION_PENDING)
 				cmd = BR_TRANSACTION_PENDING_FROZEN;
@@ -5553,7 +5553,8 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 			goto err;
 		}
 		binder_inner_proc_lock(proc);
-		proc->oneway_spam_detection_enabled = (bool)enable;
+		proc->flags &= ~PF_SPAM_DETECTION;
+		proc->flags |= enable & PF_SPAM_DETECTION;
 		binder_inner_proc_unlock(proc);
 		break;
 	}
diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h
index a22e64cddbae..3312fe93a306 100644
--- a/drivers/android/binder_internal.h
+++ b/drivers/android/binder_internal.h
@@ -434,7 +434,6 @@ struct binder_proc {
 	spinlock_t inner_lock;
 	spinlock_t outer_lock;
 	struct dentry *binderfs_entry;
-	bool oneway_spam_detection_enabled;
 };
 
 /**
diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h
index 281a8e2e734e..972f402415c2 100644
--- a/include/uapi/linux/android/binder.h
+++ b/include/uapi/linux/android/binder.h
@@ -253,7 +253,9 @@ struct binder_extended_error {
 
 /* Used with BINDER_SET_PROC_FLAGS ioctl */
 enum proc_flags {
-	PF_SUPPORTED_FLAGS_MASK,
+	PF_SPAM_DETECTION	= (1 << 0), /* enable oneway spam detection */
+
+	PF_SUPPORTED_FLAGS_MASK = PF_SPAM_DETECTION,
 };
 
 enum {
@@ -269,9 +271,11 @@ enum {
 	BINDER_SET_CONTEXT_MGR_EXT	= _IOW('b', 13, struct flat_binder_object),
 	BINDER_FREEZE			= _IOW('b', 14, struct binder_freeze_info),
 	BINDER_GET_FROZEN_INFO		= _IOWR('b', 15, struct binder_frozen_status_info),
-	BINDER_ENABLE_ONEWAY_SPAM_DETECTION	= _IOW('b', 16, __u32),
 	BINDER_GET_EXTENDED_ERROR	= _IOWR('b', 17, struct binder_extended_error),
 	BINDER_SET_PROC_FLAGS		= _IOWR('b', 18, __u32),
+
+	/* This is deprecated, use BINDER_SET_PROC_FLAGS instead. */
+	BINDER_ENABLE_ONEWAY_SPAM_DETECTION	= _IOW('b', 16, __u32),
 };
 
 /*
-- 
2.44.0.683.g7961c838ac-goog

