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 4E3E2383C86 for ; Fri, 7 Aug 2026 15:50:14 +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=1786117815; cv=none; b=KPi2q1OLqCZe3pr1m9PnjI+VFM7+zNzdPegPDFMUu0LJYFwBvKYBkhUAInEoAKA0ev9MfvJvkB+w9Yd6epZGZCY+z6bGCL2wo75IITZHhwjNJ8JqgpMlppJdwNSLhukjVF6CQExgkG9o7lqc99Yt8BA1ESUR7Kyi0WMAYbnIISo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786117815; c=relaxed/simple; bh=QbUtojPTD4aOQBSKBcz+wFCj5ZOdJ8/PhlgtI72Yvsc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LadaoUu+8dnMm8tX6p4A7b5ygqjcXyQP+gwt1lW1TsCxJbsAHNDZ04Fj9D+jgONkEc/h3vOUEp/34xDuSt0ecdrJkWd4TEvVbykuqRcoVKzBEzB73d37IM3AehWYFhq+cPG3t0Ei9/LLGWnOgNz3NhDOljzcyyM6BAZkfIMuBuw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=e4qDJR37; 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="e4qDJR37" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A5E0B1F000E9; Fri, 7 Aug 2026 15:50:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786117814; bh=cPSJpOWrP7qK8P7Gd6UkMQyChHqasekhOMlXz1EYIW0=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=e4qDJR37FZpPaqKAGA7cNDxGnxuCUmMPsTH+vDtdeVN1Uaic/2+AqPs7XgHPi4oqC FF6sCg0SydhIw3IbFWHVhPskUUW3nEGB3Dk1vV4+XH8Vn5tA3FFFgl2N1mmZq1+vpq IToBLE02tkROQgSbxkrHkI1h1nzggjVx3xgfRe3E= Date: Fri, 7 Aug 2026 16:44:59 +0200 From: Greg KH To: Matthias Merz Cc: stable@vger.kernel.org, Dong Chenchen , Steffen Klassert Subject: Re: [6.12.y] Please backport 8045c0df98d4 ("xfrm: Fix dev use-after-free in xfrm async resumption") Message-ID: <2026080738-eastward-nimbly-e78d@gregkh> References: Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Aug 07, 2026 at 04:21:55PM +0200, Matthias Merz wrote: > Hello, > > Please apply upstream commit 8045c0df98d4 ("xfrm: Fix dev use-after-free > in xfrm async resumption") also to 6.12.y. Stable 7.1.5 contains this in > 63a300151999. > > It fixes 1c428b038400 ("xfrm: hold dev ref until after transport_finish > NF_HOOK"), which is present in 6.12.y since 6.12.94. On our IPsec > gateways using xfrm interfaces this issue underflows the interface > refcount and hangs unregister_netdevice() on tunnel teardown, rekey or > system shutdown: > > unregister_netdevice: waiting for xfrm- to become free. Usage count = -381 > > This leads to a complete drop of our VPN links after some hours, and > stalls the reboot for a couple of minutes waiting for devices to become > free (I remember waiting 10-15 minutes for the shutdown when remote > rebooting a gateway without physical access) > > known affected: 6.12.96 and 6.12.96, known unaffected 6.12.90 > Fixed in 7.1.5 via 63a300151999. It does not apply cleanly to those trees, please provide a working backport that you have tested and we will be glad to apply it. thanks, greg k-h