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 2CA093101A6; Sun, 7 Jun 2026 10:05:46 +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=1780826749; cv=none; b=Z8qx2/y/iFJqjcgxR4mwG5Wy6kMwVbhZNGBn5I3m60EMYr76RsriarAHwqeZDNtBimE89H+0cJ4Ib+A5VVwN1c16hMpxOYD9SeCJ71UC8Yj/8LPlMLFoCxphmaivQOBpfxVwoe7pPi/MLFTJP4wDm7fANGLksnPkQYyNrL0nEew= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780826749; c=relaxed/simple; bh=OazCAWbRiAVS43dgjaT3w9pPUW4FujXBag5g3LnlGeM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Fl569mi9Cgsy2Lp4v3vmTVm8YSyVC7XrHWon5iK7Ic+LekrDIFbD8NVA0q1pTYTpO2DxuRwQzlk0hNQlbkzaeRkGPax7okjFn02wc4vGthdmkVPOa4EWwQxacJwkwZ6ARHx21OsPE04HiL7S9ZNxXcMSX+TrrHoduoSv8MK61Jk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MUMabSPY; 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="MUMabSPY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 30ADD1F00893; Sun, 7 Jun 2026 10:05:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780826746; bh=MwdvGBf7Sgibsn5vg5mWG2pyHXY3pZT9y4IupFa3A94=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MUMabSPYGjGP9PadY8A45HtgCdEZzpbAgEGUFGu1Eg4CV2RatDDLfnPhjSsMLCc4r RlQlT1t6+oPNuxWR5UVb6BRzgI7q+/zrwSzl+OlriDL6pfbVTiWKqVywK2Z20UZCZq M5OpjQrsBWy5xt8bVDq1Cki+h1IjN0HDa5andizE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alessandro Schino <7991aleschino@gmail.com>, Steffen Klassert , Sasha Levin Subject: [PATCH 7.0 016/332] esp: fix page frag reference leak on skb_to_sgvec failure Date: Sun, 7 Jun 2026 11:56:25 +0200 Message-ID: <20260607095728.644422375@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095728.031258202@linuxfoundation.org> References: <20260607095728.031258202@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 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: e521588 [ Upstream commit 2982e599fff6faa21c8df147d96fc7af6c1a2f24 ] In esp_output_tail(), when esp->inplace is false, the old skb page frags are replaced with a new page from the xfrm page_frag cache. The source scatterlist (sg) is built from the old frags before the replacement, and esp_ssg_unref() is responsible for releasing the old page references after the crypto operation completes. However, if the second skb_to_sgvec() call (which builds the destination scatterlist from the new page) fails, the code jumps to error_free which only calls kfree(tmp). The old page frag references captured in the source scatterlist are never released: 1. sg[] is built from old frags via skb_to_sgvec() (no extra get_page) 2. nr_frags is set to 1 and frag[0] is replaced with the new page 3. Second skb_to_sgvec() fails -> goto error_free 4. kfree(tmp) frees the sg[] memory but old frags are not unref'd 5. kfree_skb() only releases frag[0] (the new page), not the old ones Fix this by adding a bool parameter to esp_ssg_unref() that, when true, unconditionally unrefs the source scatterlist frags without checking req->src and req->dst, since those fields are not yet initialized by aead_request_set_crypt() at the point of the error. Existing callers pass false to preserve the original behavior. The same issue exists in both esp4 and esp6 as the code is identical. Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible") Signed-off-by: Alessandro Schino <7991aleschino@gmail.com> Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- net/ipv4/esp4.c | 12 +++++++----- net/ipv6/esp6.c | 12 +++++++----- 2 files changed, 14 insertions(+), 10 deletions(-) diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 6a5febbdbee493..8314d7bddcb715 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -96,7 +96,7 @@ static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, __alignof__(struct scatterlist)); } -static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb) +static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb, bool already_unref) { struct crypto_aead *aead = x->data; int extralen = 0; @@ -113,7 +113,7 @@ static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb) /* Unref skb_frag_pages in the src scatterlist if necessary. * Skip the first sg which comes from skb->data. */ - if (req->src != req->dst) + if (already_unref || req->src != req->dst) for (sg = sg_next(req->src); sg; sg = sg_next(sg)) skb_page_unref(page_to_netmem(sg_page(sg)), skb->pp_recycle); @@ -220,7 +220,7 @@ static void esp_output_done(void *data, int err) } tmp = ESP_SKB_CB(skb)->tmp; - esp_ssg_unref(x, tmp, skb); + esp_ssg_unref(x, tmp, skb, false); kfree(tmp); if (xo && (xo->flags & XFRM_DEV_RESUME)) { @@ -569,8 +569,10 @@ int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * err = skb_to_sgvec(skb, dsg, (unsigned char *)esph - skb->data, assoclen + ivlen + esp->clen + alen); - if (unlikely(err < 0)) + if (unlikely(err < 0)) { + esp_ssg_unref(x, tmp, skb, true); goto error_free; + } } if ((x->props.flags & XFRM_STATE_ESN)) @@ -602,7 +604,7 @@ int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * } if (sg != dsg) - esp_ssg_unref(x, tmp, skb); + esp_ssg_unref(x, tmp, skb, false); if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP) err = esp_output_tail_tcp(x, skb); diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c index 9c06c5a1419dc4..9d0c4957ac6276 100644 --- a/net/ipv6/esp6.c +++ b/net/ipv6/esp6.c @@ -113,7 +113,7 @@ static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, __alignof__(struct scatterlist)); } -static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb) +static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb, bool already_unref) { struct crypto_aead *aead = x->data; int extralen = 0; @@ -130,7 +130,7 @@ static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb) /* Unref skb_frag_pages in the src scatterlist if necessary. * Skip the first sg which comes from skb->data. */ - if (req->src != req->dst) + if (already_unref || req->src != req->dst) for (sg = sg_next(req->src); sg; sg = sg_next(sg)) skb_page_unref(page_to_netmem(sg_page(sg)), skb->pp_recycle); @@ -254,7 +254,7 @@ static void esp_output_done(void *data, int err) } tmp = ESP_SKB_CB(skb)->tmp; - esp_ssg_unref(x, tmp, skb); + esp_ssg_unref(x, tmp, skb, false); kfree(tmp); esp_output_encap_csum(skb); @@ -600,8 +600,10 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info err = skb_to_sgvec(skb, dsg, (unsigned char *)esph - skb->data, assoclen + ivlen + esp->clen + alen); - if (unlikely(err < 0)) + if (unlikely(err < 0)) { + esp_ssg_unref(x, tmp, skb, true); goto error_free; + } } if ((x->props.flags & XFRM_STATE_ESN)) @@ -634,7 +636,7 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info } if (sg != dsg) - esp_ssg_unref(x, tmp, skb); + esp_ssg_unref(x, tmp, skb, false); if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP) err = esp_output_tail_tcp(x, skb); -- 2.53.0