From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793699696; b=RD/L7T96O9Q6c4nAX40CBdtf6DJZJpMU907W21RWckog4umlkUNj+NrI7LO4Qvhacgl8 e8JF9I38CByoFWxezlOg1fPznEv5i1P/rQ35DUEG9UFl3QEzYXnybthv5BSeurBAKLAAF Ry8Zw+8lsug+SmDcZSZnJ8kzJaYiIVx7+P2yhLb0hQE3Kp9A1yPEBWixWaG4eAmI//sS3 YfxYuWf7hfhoKwoKfcVYDm+qEvZTG9xVZpGQuXrwNHAvDbVNUGuOo/qF077G6TOHwoxjw cyz9nVRPowqHJlaKTZpAf6JX6Qb4my8gzlgJlN/I/MZBSn8vzWn3s8c39k8u8TO5kqQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793699696; h=Received:DKIM-Signature:From:To:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=7O3qK6NQZiMzw6jt5TU0sGJN/nyeWM0XPpYnj5iMF0A=; b=ZCsgr3BzSqOreB22lxfHesbo7jO3GvWJyAjd02K6BhAXvH+mTgs1QLcZgsuNUFoF3MpO RdrPAYhI5dgtcnCmt1uLtO1gFqtB/xotTBqqr1CtSOVlIjfMQ5oh3xZQexzCkon4W5+Po OVJ203UzmtMRbcq85r09svb3C3ZruUSKsnbjTjRHkE9avNSt+B+buHwNI2e37P1AH4vU7 54VdO1hEUpXHIS2vsTRd2pnPrZ0fwub02+J2KRFZKqrkZlOW4bhVM0qy+H/QO551EZ3Y7 LLLuxEnDOae5rt74KLMTD4Jej9A5mG+RM3xZXCFfSs3bENs3ixfVEe7Yu8y4hYrUKQQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="g+C8K/jo"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 06D6D606EEBD; Tue, 3 Nov 2026 09:54:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=g+C8K/jo Received: by smtp.kernel.org (Postfix) with ESMTPSA id 929B71F000C1; Tue, 3 Nov 2026 09:54:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793699695; bh=7O3qK6NQZiMzw6jt5TU0sGJN/nyeWM0XPpYnj5iMF0A=; h=From:To:Subject:Date:In-Reply-To:References; b=g+C8K/jomsZefw1qcVsmBeaODrK+U3vuhGwdWYqNycpGmzXhpngBmIfn9QIDh7IWi x8HX2TfBKL4FjvZJUqYLwYvvOHp4kU2ikHnNIyHoj33RtLWqnyWpmo2wrZr3fZMOpx qB59s6Ln8ayr5PL9RfqDJmqTM4hSW6/jYdulM6rvhdqr1XdJePdR6njuorM501eL30 sPdEbsQqhQc0uzCRo2AgVeEeDT2fYD3p6lJ2XbJo6eCkrAqbYO0v7NMYkjmC+pR5Zk zu5J7D0O3/z3B4uUM/AA4ilzIQFe0627vWBCB0tJNu3ESoUJkCQ+Dg19cSD+QXR7zT Lh2BfR0xSreIA== From: Lee Jones To: lee@kernel.org, Vinod Koul , Bard Liao , Pierre-Louis Bossart , linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 01/10] soundwire: bus: Hold bus_lock when looking up slave devices Date: Tue, 3 Nov 2026 09:53:45 +0000 Message-ID: <20261103095445.81414-2-lee@kernel.org> X-Mailer: git-send-email 2.56.0.385.gac671c819a-goog In-Reply-To: <20261103095445.81414-1-lee@kernel.org> References: <20261103095445.81414-1-lee@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit sdw_get_slave() iterates over bus->slaves and requires bus->bus_lock to be held by the caller. However, sdw_handle_slave_status() and sdw_clear_slave_status() drop bus->bus_lock immediately before calling sdw_get_slave(). If a concurrent slave teardown unlinks the node via list_del_init() and frees the slave while bus->bus_lock is dropped, sdw_get_slave() can spin forever on the self-referential list entry or dereference freed memory. Keep bus->bus_lock held across the sdw_get_slave() lookup in sdw_handle_slave_status() and sdw_clear_slave_status(). Closes: https://sashiko.dev/#/bug/linux-b0e65a93-dfd4-4e3d-a96c-8f13ba0aafd2 Signed-off-by: Lee Jones --- v1 => v2: Drop Fixes and Stable tags drivers/soundwire/bus.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index aeaae5a57c89..15c66effbf4f 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -1907,9 +1907,9 @@ int sdw_handle_slave_status(struct sdw_bus *bus, mutex_unlock(&bus->bus_lock); continue; } - mutex_unlock(&bus->bus_lock); slave = sdw_get_slave(bus, i); + mutex_unlock(&bus->bus_lock); if (!slave) continue; @@ -1954,9 +1954,9 @@ int sdw_handle_slave_status(struct sdw_bus *bus, mutex_unlock(&bus->bus_lock); continue; } - mutex_unlock(&bus->bus_lock); slave = sdw_get_slave(bus, i); + mutex_unlock(&bus->bus_lock); if (!slave) continue; @@ -2052,9 +2052,9 @@ void sdw_clear_slave_status(struct sdw_bus *bus, u32 request) mutex_unlock(&bus->bus_lock); continue; } - mutex_unlock(&bus->bus_lock); slave = sdw_get_slave(bus, i); + mutex_unlock(&bus->bus_lock); if (!slave) continue; -- 2.56.0.385.gac671c819a-goog