From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B4B7F2F8BC3; Mon, 13 Apr 2026 16:16:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776097013; cv=none; b=YvjdmhhKUdfw51S2gICO/zINBZsCNhsCeAOuxx62b7VlTtcP69luj/A9L9DKj0Nvd976Ine+40FB+I1vBxea6PeTZYIrNt5vabLPwCHpisk7sv4koAHHFbjmvXLTpJ5cU2z50a8mwMfZZUmdgMU1wvfoG6EGhO8hR+wSGNGiglA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776097013; c=relaxed/simple; bh=zA1jG+4ADxSQdOvijRkhCHP7DZFyneMI1RRLo7nkABQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pGYIEiR3lxvIC5XP0T1/Ep617CkaPgy1EZ5fs9dgIisP1GtaTlxLdjUIYd6iRZXX1XYabsbaucGW3C1zFVhFvE2yixo/+KmU5tCqyDCvAdFGZhl/fACPTOLQfOTMILXk5D5936ln7kinHHfzn6IXxu3PIjXw1gwxx6VXw5UY1/Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sb+8xjIX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="sb+8xjIX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 48595C2BCAF; Mon, 13 Apr 2026 16:16:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776097013; bh=zA1jG+4ADxSQdOvijRkhCHP7DZFyneMI1RRLo7nkABQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sb+8xjIXGD2yNbx/v5dFIn8jB8nj4PaooaWpiLYXzTudsFgH0UezMcF9QPX5IRjOU ZipkPxPOiKoZphFR7WP46jh5AX/FP9kkgdLauBPZENHXKWRddlk5reSv26BP+uEOaP lzUfE89b1iu8cd5DgK5ozCq+1a2v5XZ/cTe0IJPs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Johannes Berg , Sasha Levin Subject: [PATCH 6.1 29/55] rfkill: sync before userspace visibility/changes Date: Mon, 13 Apr 2026 18:01:03 +0200 Message-ID: <20260413155725.921664479@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260413155724.820472494@linuxfoundation.org> References: <20260413155724.820472494@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg [ Upstream commit 2c3dfba4cf84ac4f306cc6653b37b6dd6859ae9d ] If userspace quickly opens /dev/rfkill after a new instance was created, it might see the old state of the instance from before the sync work runs and may even _change_ the state, only to have the sync work change it again. Fix this by doing the sync inline where needed, not just for /dev/rfkill but also for sysfs. Signed-off-by: Johannes Berg Stable-dep-of: ea245d78dec5 ("net: rfkill: prevent unlimited numbers of rfkill events from being created") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/rfkill/core.c | 32 ++++++++++++++++++++++++++------ 1 file changed, 26 insertions(+), 6 deletions(-) --- a/net/rfkill/core.c +++ b/net/rfkill/core.c @@ -48,6 +48,7 @@ struct rfkill { bool persistent; bool polling_paused; bool suspended; + bool need_sync; const struct rfkill_ops *ops; void *data; @@ -368,6 +369,17 @@ static void rfkill_set_block(struct rfki rfkill_event(rfkill); } +static void rfkill_sync(struct rfkill *rfkill) +{ + lockdep_assert_held(&rfkill_global_mutex); + + if (!rfkill->need_sync) + return; + + rfkill_set_block(rfkill, rfkill_global_states[rfkill->type].cur); + rfkill->need_sync = false; +} + static void rfkill_update_global_state(enum rfkill_type type, bool blocked) { int i; @@ -730,6 +742,10 @@ static ssize_t soft_show(struct device * { struct rfkill *rfkill = to_rfkill(dev); + mutex_lock(&rfkill_global_mutex); + rfkill_sync(rfkill); + mutex_unlock(&rfkill_global_mutex); + return sysfs_emit(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0); } @@ -751,6 +767,7 @@ static ssize_t soft_store(struct device return -EINVAL; mutex_lock(&rfkill_global_mutex); + rfkill_sync(rfkill); rfkill_set_block(rfkill, state); mutex_unlock(&rfkill_global_mutex); @@ -783,6 +800,10 @@ static ssize_t state_show(struct device { struct rfkill *rfkill = to_rfkill(dev); + mutex_lock(&rfkill_global_mutex); + rfkill_sync(rfkill); + mutex_unlock(&rfkill_global_mutex); + return sysfs_emit(buf, "%d\n", user_state_from_blocked(rfkill->state)); } @@ -805,6 +826,7 @@ static ssize_t state_store(struct device return -EINVAL; mutex_lock(&rfkill_global_mutex); + rfkill_sync(rfkill); rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED); mutex_unlock(&rfkill_global_mutex); @@ -1032,14 +1054,10 @@ static void rfkill_uevent_work(struct wo static void rfkill_sync_work(struct work_struct *work) { - struct rfkill *rfkill; - bool cur; - - rfkill = container_of(work, struct rfkill, sync_work); + struct rfkill *rfkill = container_of(work, struct rfkill, sync_work); mutex_lock(&rfkill_global_mutex); - cur = rfkill_global_states[rfkill->type].cur; - rfkill_set_block(rfkill, cur); + rfkill_sync(rfkill); mutex_unlock(&rfkill_global_mutex); } @@ -1087,6 +1105,7 @@ int __must_check rfkill_register(struct round_jiffies_relative(POLL_INTERVAL)); if (!rfkill->persistent || rfkill_epo_lock_active) { + rfkill->need_sync = true; schedule_work(&rfkill->sync_work); } else { #ifdef CONFIG_RFKILL_INPUT @@ -1171,6 +1190,7 @@ static int rfkill_fop_open(struct inode ev = kzalloc(sizeof(*ev), GFP_KERNEL); if (!ev) goto free; + rfkill_sync(rfkill); rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD); list_add_tail(&ev->list, &data->events); }