From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 56CB23911A9; Sat, 17 Oct 2026 17:06:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792256766; cv=none; b=EJJ2aePyisyfOcLksCG+SgzsDaq9/2ugtY0oy5Hmi9GbffW392vcZSbphID5iWbNu5ovlSSSAnC6Or65yAKJv7u1zake7oTejjTwCJpVypXb+T3O5O878qKbM54lhTLr6KxiC56KqxK6Cz8J/jJcRQUSFdH9NtgMzQ+JxNxU+WA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792256766; c=relaxed/simple; bh=yC3Ubce2WwaZLWvnhJk78dzC1seAQNgDSk/dzBrwMhE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EgZDEMKKanGZzv2TWfXOdJLaWofOptWRNc0vd0wCFl3i32OkMP0EwCuEwIJWDlSvq4RzD9cefIE1kWRlx/oJwUSUb/t4FZqGmPOk8KKcBfQn0P0shaIOHVMHVvOD/oVlHfwTsbtqG3F5tqFKI+u9SolCdhMT1j18d7sOY3iQOP4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hGxUp5k5; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="hGxUp5k5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0095F1F000C4; Sat, 17 Oct 2026 17:06:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792256764; bh=8ImTcgHJeJV8jwt/joz4fKQ6bEMmXxBkIqd+dzxOT3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=hGxUp5k5fglujONg10kWPxFjxFFm15yGhR4fZmy0SRuQqpJ6Q0VIYSQtT0lxp0Zfo /9Kk0eHzXo0+QiKNkKA78S0GfrrLkJaj4yoyswg7/zzgsotRa/8ug1GC+emObHs2NF MsSCtF51cT1mIDfrPr2lDO45sbbc6tbcXH0j89nE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sashiko AI review , Aldo Ariel Panzardo , Benjamin Tissoires , Sasha Levin Subject: [PATCH 6.6 0302/1674] HID: multitouch: stop the release timer from being rearmed on remove Date: Sat, 17 Oct 2026 17:42:54 +0200 Message-ID: <20261017160438.871477794@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160431.119607952@linuxfoundation.org> References: <20261017160431.119607952@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aldo Ariel Panzardo [ Upstream commit 5acb2dace582f061aab5e14c399ac9480315f44b ] mt_remove() quiesces the sticky-finger timer before stopping the hardware: timer_delete_sync(&td->release_timer); sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group); hid_hw_stop(hdev); timer_delete_sync() waits for a running callback and dequeues the timer, but it does not stop the timer from being armed again. The transport is still delivering reports at that point, and the report path rearms it: if (app->quirks & MT_QUIRK_STICKY_FINGERS) { if (td->mt_io_flags & MT_IO_SLOTS_MASK) mod_timer(&td->release_timer, jiffies + msecs_to_jiffies(100)); A report that arrives after timer_delete_sync() has returned therefore leaves the timer queued. td is allocated with devm_kzalloc() against hdev->dev, so it is freed when the driver is unbound, after mt_remove() returns. When the timer fires afterwards, mt_expired_timeout() dereferences the freed td: struct mt_device *td = timer_container_of(td, t, release_timer); struct hid_device *hdev = td->hdev; if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags)) Simply moving the teardown after hid_hw_stop() does not fix this on its own, because mt_expired_timeout() calls mt_release_contacts(), which walks hdev->inputs; the timer still has to be quiesced before hid_hw_stop() tears the input devices down. Use timer_shutdown_sync() instead, which additionally makes any later mod_timer() a no-op, so neither ordering constraint has to be traded off against the other. This is the final-teardown pattern the function was introduced for, and hid-wiimote already uses it for the same reason. Fixes: 4f4001bc76fd ("HID: multitouch: fix rare Win 8 cases when the touch up event gets missing") Cc: stable@vger.kernel.org Reported-by: Sashiko AI review Closes: https://sashiko.dev/#/patchset/20260723224211.613112-1-you@example.com?part=1 Signed-off-by: Aldo Ariel Panzardo Reviewed-by: Benjamin Tissoires Signed-off-by: Benjamin Tissoires [ sashal: Adapted the patch to replace del_timer_sync() instead of timer_delete_sync(). ] Signed-off-by: Sasha Levin --- drivers/hid/hid-multitouch.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 4481bf5c9133d..422172ecf2bb2 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -1895,7 +1895,7 @@ static void mt_remove(struct hid_device *hdev) { struct mt_device *td = hid_get_drvdata(hdev); - del_timer_sync(&td->release_timer); + timer_shutdown_sync(&td->release_timer); sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group); hid_hw_stop(hdev); -- 2.53.0