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 73A4D26B0A9; Tue, 16 Jun 2026 15:22:18 +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=1781623339; cv=none; b=KehpEyeJnue5ukthmjQFer5hlogfHU6YMT4w6FpAIHxU87SWm3rFF4yQF4/e+LuL28JJZBQr22NDZXp53Htel+Rh1YY3NzLWUaTwmPj9kUP04jSDTTNtynelTxPpofCCn6VXYEIQh2s28IElfvMlU3xi7o4+B7a7rC/SFw6Eyg0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781623339; c=relaxed/simple; bh=DukH3FfDqjsXZYdcM0AkxLAkQ1juPXyXeBn8024xfH4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fphwbXFH2zk0JSkhqcPrFbQF07TrmHmQE543f9s54ESx4jndU0yW9TkEMr7ahR2Fv1Eco/qaZmyyJ+hjyFGcdGW4sR6+1abh3rzEcLfFJAyoXMBnfmxYESj8AGpqzeBb8TjtJULC128xiu1E9qgUZdP9djFM15GBJP+6CE0nKGk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OuK09b4B; 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="OuK09b4B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7511E1F000E9; Tue, 16 Jun 2026 15:22:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781623338; bh=2HsvlnynqSey3w5jDpO/q3ALvuscg06VbHDahAP+rLo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OuK09b4B1xcUsm4HexFzTx9GslPkc5CEcosKRfFYhoSxU+j1pdvqudbs7oSyAyiZ4 riHJAPMSZ2BsqvKwsVBvBIIdFBMnJXtVEJaVQbeF3YIJXzRLfULJtlEPSIhhMW4Kxj yQgEQb88JsEJwR5apgLhkTlHWCn+ty+5WMauYiik= 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 7.0 129/378] esp: fix page frag reference leak on skb_to_sgvec failure Date: Tue, 16 Jun 2026 20:26:00 +0530 Message-ID: <20260616145117.113400641@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145109.744539446@linuxfoundation.org> References: <20260616145109.744539446@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: Alessandro Schino <7991aleschino@gmail.com> [ 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 Stable-dep-of: 26aad08a9289 ("esp: fix page frag reference leak on skb_to_sgvec failure") Signed-off-by: Sasha Levin --- net/ipv4/esp4.c | 17 +++++++++++------ net/ipv6/esp6.c | 17 +++++++++++------ 2 files changed, 22 insertions(+), 12 deletions(-) diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 513c8215c947f1..dfc81ee969ae03 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; @@ -113,10 +113,13 @@ 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) - for (sg = sg_next(req->src); sg; sg = sg_next(sg)) + if (already_unref || req->src != req->dst) { + struct scatterlist *src = already_unref ? esp_req_sg(aead, req) : req->src; + + for (sg = sg_next(src); sg; sg = sg_next(sg)) skb_page_unref(page_to_netmem(sg_page(sg)), skb->pp_recycle); + } } #ifdef CONFIG_INET_ESPINTCP @@ -220,7 +223,7 @@ 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 +572,10 @@ 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 +607,7 @@ 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 57481e423e59e6..296b57926abb98 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; @@ -130,10 +130,13 @@ 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) - for (sg = sg_next(req->src); sg; sg = sg_next(sg)) + if (already_unref || req->src != req->dst) { + struct scatterlist *src = already_unref ? esp_req_sg(aead, req) : req->src; + + for (sg = sg_next(src); sg; sg = sg_next(sg)) skb_page_unref(page_to_netmem(sg_page(sg)), skb->pp_recycle); + } } #ifdef CONFIG_INET6_ESPINTCP @@ -254,7 +257,7 @@ 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 +603,10 @@ 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 +639,7 @@ 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