From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [91.216.245.30]) (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 77D7236C0DB; Fri, 13 Mar 2026 15:06:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.216.245.30 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773414415; cv=none; b=MMWBk7maPtCnFpCrZISR8g0fsM7nQwPq9wuDFV4wtHRZzXmsVyHsRJwzmFBIDsrvTKTcNmowX8Cd7zwgxy4zssNPdTt4V2WmYGXpMEbgVA6eeN3U9by+i3ZBGf4UTArhfNrLITYw0qaTyNjfwsRxIhTrjGpEW1KI5UrPbV7cw6A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773414415; c=relaxed/simple; bh=mkJcw+TeOQSRxJqwnx82dcAWGt985JTdVnnKwkl2RYk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lRDOiSelSDuEj7snu0Ua/Lw+loa1CaEnZvCs5+8aGREibwy/pbalTCG1OVNe9+V18IqOvltc4YlT8rezthL1PJ9N0Pju3X12r0zL4OmkBYw4g6+yBbZvvNEk6NVhuGWABdJV69cyAv0STdZJ3XU981P7h3ExdgGvMzWXwKMuyp8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de; spf=pass smtp.mailfrom=Chamillionaire.breakpoint.cc; arc=none smtp.client-ip=91.216.245.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=Chamillionaire.breakpoint.cc Received: by Chamillionaire.breakpoint.cc (Postfix, from userid 1003) id EF6016047A; Fri, 13 Mar 2026 16:06:51 +0100 (CET) From: Florian Westphal To: Cc: Paolo Abeni , "David S. Miller" , Eric Dumazet , Jakub Kicinski , , pablo@netfilter.org Subject: [PATCH net 07/11] nf_tables: nft_dynset: fix possible stateful expression memleak in error path Date: Fri, 13 Mar 2026 16:06:10 +0100 Message-ID: <20260313150614.21177-8-fw@strlen.de> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260313150614.21177-1-fw@strlen.de> References: <20260313150614.21177-1-fw@strlen.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Pablo Neira Ayuso If cloning the second stateful expression in the element via GFP_ATOMIC fails, then the first stateful expression remains in place without being released.   unreferenced object (percpu) 0x607b97e9cab8 (size 16):     comm "softirq", pid 0, jiffies 4294931867     hex dump (first 16 bytes on cpu 3):       00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     backtrace (crc 0):       pcpu_alloc_noprof+0x453/0xd80       nft_counter_clone+0x9c/0x190 [nf_tables]       nft_expr_clone+0x8f/0x1b0 [nf_tables]       nft_dynset_new+0x2cb/0x5f0 [nf_tables]       nft_rhash_update+0x236/0x11c0 [nf_tables]       nft_dynset_eval+0x11f/0x670 [nf_tables]       nft_do_chain+0x253/0x1700 [nf_tables]       nft_do_chain_ipv4+0x18d/0x270 [nf_tables]       nf_hook_slow+0xaa/0x1e0       ip_local_deliver+0x209/0x330 Fixes: 563125a73ac3 ("netfilter: nftables: generalize set extension to support for several expressions") Reported-by: Gurpreet Shergill Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- include/net/netfilter/nf_tables.h | 2 ++ net/netfilter/nf_tables_api.c | 4 ++-- net/netfilter/nft_dynset.c | 10 +++++++++- 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 6299af4ef423..ec8a8ec9c0aa 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -874,6 +874,8 @@ struct nft_elem_priv *nft_set_elem_init(const struct nft_set *set, u64 timeout, u64 expiration, gfp_t gfp); int nft_set_elem_expr_clone(const struct nft_ctx *ctx, struct nft_set *set, struct nft_expr *expr_array[]); +void nft_set_elem_expr_destroy(const struct nft_ctx *ctx, + struct nft_set_elem_expr *elem_expr); void nft_set_elem_destroy(const struct nft_set *set, const struct nft_elem_priv *elem_priv, bool destroy_expr); diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 4ccdd33cf133..9b1c8d0a35fb 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -6744,8 +6744,8 @@ static void __nft_set_elem_expr_destroy(const struct nft_ctx *ctx, } } -static void nft_set_elem_expr_destroy(const struct nft_ctx *ctx, - struct nft_set_elem_expr *elem_expr) +void nft_set_elem_expr_destroy(const struct nft_ctx *ctx, + struct nft_set_elem_expr *elem_expr) { struct nft_expr *expr; u32 size; diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index 7807d8129664..9123277be03c 100644 --- a/net/netfilter/nft_dynset.c +++ b/net/netfilter/nft_dynset.c @@ -30,18 +30,26 @@ static int nft_dynset_expr_setup(const struct nft_dynset *priv, const struct nft_set_ext *ext) { struct nft_set_elem_expr *elem_expr = nft_set_ext_expr(ext); + struct nft_ctx ctx = { + .net = read_pnet(&priv->set->net), + .family = priv->set->table->family, + }; struct nft_expr *expr; int i; for (i = 0; i < priv->num_exprs; i++) { expr = nft_setelem_expr_at(elem_expr, elem_expr->size); if (nft_expr_clone(expr, priv->expr_array[i], GFP_ATOMIC) < 0) - return -1; + goto err_out; elem_expr->size += priv->expr_array[i]->ops->size; } return 0; +err_out: + nft_set_elem_expr_destroy(&ctx, elem_expr); + + return -1; } struct nft_elem_priv *nft_dynset_new(struct nft_set *set, -- 2.52.0