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 EC3E436E467; Wed, 30 Sep 2026 19:27:25 +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=1790796447; cv=none; b=H9LgWr1a/KOm1J0gBOt0K7MIR+vFIm30y1OU+NI8fflf8eLqWhKNKiGkeM/b/wbOxwNhuFKsXLe0eGggHFMdSeiCVarUV9nrW+qMpx56FVK7RTCjWFVCe/bljHV5ZwXP7V+/fpXlnYGhbSLyOTdJi7dnh6R2hGXyyJ6yD8q4oXc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790796447; c=relaxed/simple; bh=9Wuyv259v9Ps6E3/TLKPBYu1qzZ0jlBLzDfQeDWbiww=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=te89TpNYrfyJPY+aD6TRPUKsiCLUJ1GUbJj0Sfxf+O/tjo44VMnTN4YodfqXbuUN61g2vMjneMQj5u6qgKf2jX+JXzQxm/KBoSH+DhhC/1oppvbHaxrZDcYmeBr6rxWhzVfsJmhWVvQt0C8+8ZrRlUJsTTNSskAWa6ENh9mNuKk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XZnzEYTn; 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="XZnzEYTn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C9771F000FF; Wed, 30 Sep 2026 19:27:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790796445; bh=7CNMCbvuHa4kURvjHpYiEm3I++RAt3LRxuZd9a9tMoE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XZnzEYTn6j99YSu1x+bxoP6239pG+lNYwl9vqQjZlTIu19H890gvU9UkkkEJbYOTl PJfDo3s71yTR0l+jE8ceQUSKixtKrNRpH1j8k4MBq7VMlu46qalahyJNPxdCpgAa9B qCpepHMM20OaMOWTh+uIlhLaVsA0QsSUsaKG/g48= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jiangshan Yi , Arend van Spriel , Johannes Berg Subject: [PATCH 6.6 0917/1193] wifi: brcmsmac: fix UAF in brcms_free_timer() Date: Wed, 30 Sep 2026 17:26:41 +0200 Message-ID: <20260930152454.613369967@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152434.301151190@linuxfoundation.org> References: <20260930152434.301151190@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: Jiangshan Yi commit 1eeca1d5e0920fbdad6449768fd2d4364e714180 upstream. brcms_free_timer() calls brcms_del_timer() which uses the non-synchronous cancel_delayed_work() to cancel the timer's underlying delayed work. If the work callback (_brcms_timer) is already running, cancel_delayed_work() returns false without waiting, and brcms_free_timer() proceeds to kfree(t) while the callback still accesses t through container_of(). Add an explicit cancel_delayed_work_sync() after brcms_del_timer() to guarantee that any in-flight callback has completed before the timer structure is freed. Fixes: 5b435de0d786 ("net: wireless: add brcm80211 drivers") Cc: stable@vger.kernel.org Signed-off-by: Jiangshan Yi Acked-by: Arend van Spriel Link: https://patch.msgid.link/20260815121043.938414-1-yijiangshan@kylinos.cn Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/broadcom/brcm80211/brcmsmac/mac80211_if.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/mac80211_if.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/mac80211_if.c @@ -1565,6 +1565,10 @@ void brcms_free_timer(struct brcms_timer /* delete the timer in case it is active */ brcms_del_timer(t); + /* Ensure the callback has finished before freeing the timer + * structure, since brcms_del_timer() uses non-synchronous cancel. + */ + cancel_delayed_work_sync(&t->dly_wrk); if (wl->timers == t) { wl->timers = wl->timers->next;