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 A343F36F421; Wed, 20 May 2026 17:19:55 +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=1779297596; cv=none; b=jFYLEHsCeinhawChW+3hkKm7fk8bnuKxPkgkmZazEuMs2KmBCSzoEqJZftK9GtHQjxflKtCg5CgzPqR/NpAYau+wGGMP2qZeg4191qA+opsEmtQ2mcdOtT8VAjHayIqghVgoPuN/sIrVuEtDyE8LgtbmoGcDem7Nf1x0qltZvAs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297596; c=relaxed/simple; bh=8x74QNmQIfmsbOgOy9sTyS5OJo5Fi59DJIWaauETS8o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kn1sBMmF+wvmpzx/uH5q/5RL6J0j86DLKvEzaKj72ttNEoBsbELcVND46ujZfuQgdSoT+NcpjPAYk4P+DzQGabRrHgJnvigSRWRmq2GngFQpAC23/j+Fh8kd/Hlq2vN+mvLEkk2KJKg2fdgiplH0w7fPfWj/HrsOK0V/Ydb62sk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dg9rHsjn; 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="dg9rHsjn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13D431F000E9; Wed, 20 May 2026 17:19:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779297595; bh=KYoErrZ4Xsy1PKguyYQAEQKNPiUTrMs1lh9rl8dxu7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=dg9rHsjnw6/8N8eJzatNvV0gNGHr0acEmRg1g0UeHdt2UyXKPEz4jxL856E55nHHI lRlHjnFxM8TOV37V60NJiXnP+1vpaAY6pV2rrcBFzkR/oLSUVvEXavrHZI4XwtIn6O nk8tiAEJERR7QdpuQVYvJZ8I1W294Kc+i272vZQA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Quan Zhou , Sean Wang , Felix Fietkau , Sasha Levin Subject: [PATCH 6.18 092/957] wifi: mt76: mt7921: fix potential deadlock in mt7921_roc_abort_sync Date: Wed, 20 May 2026 18:09:35 +0200 Message-ID: <20260520162136.554692741@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162134.554764788@linuxfoundation.org> References: <20260520162134.554764788@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Wang [ Upstream commit d5059e52fd8bc624ec4255c9fa01a266513d126b ] roc_abort_sync() can deadlock with roc_work(). roc_work() holds dev->mt76.mutex, while cancel_work_sync() waits for roc_work() to finish. If the caller already owns the same mutex, both sides block and no progress is possible. This deadlock can occur during station removal when mt76_sta_state() -> mt76_sta_remove() -> mt7921_mac_sta_remove() -> mt7921_roc_abort_sync() invokes cancel_work_sync() while roc_work() is still running and holding dev->mt76.mutex. This avoids the mutex deadlock and preserves exactly-once work ownership. Fixes: 352d966126e6 ("wifi: mt76: mt7921: fix a potential association failure upon resuming") Co-developed-by: Quan Zhou Signed-off-by: Quan Zhou Signed-off-by: Sean Wang Link: https://patch.msgid.link/20260126180013.8167-1-sean.wang@kernel.org Signed-off-by: Felix Fietkau Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt76/mt7921/main.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c index ea6ff4c6bc90b..07495c97f1c12 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c @@ -371,12 +371,15 @@ void mt7921_roc_abort_sync(struct mt792x_dev *dev) { struct mt792x_phy *phy = &dev->phy; + if (!test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state)) + return; + timer_delete_sync(&phy->roc_timer); - cancel_work_sync(&phy->roc_work); - if (test_and_clear_bit(MT76_STATE_ROC, &phy->mt76->state)) - ieee80211_iterate_interfaces(mt76_hw(dev), - IEEE80211_IFACE_ITER_RESUME_ALL, - mt7921_roc_iter, (void *)phy); + cancel_work(&phy->roc_work); + + ieee80211_iterate_interfaces(mt76_hw(dev), + IEEE80211_IFACE_ITER_RESUME_ALL, + mt7921_roc_iter, (void *)phy); } EXPORT_SYMBOL_GPL(mt7921_roc_abort_sync); -- 2.53.0