From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E6F47336EE1; Mon, 20 Apr 2026 15:57:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776700625; cv=none; b=BaNMR+ExH/45TNdGoGTeFK5Qx/96NMjgQ1WnkyrfAmYAakF4pKOc8XzY8a4rGXhGOcBJojgsOwh+mVdgBaiVSkDxLsWZ3IKceP8DW75G/kypAtYvCsak9EhFtpXDqm46NtXhLrYZMefVwGTTVizpFQt3G9FVRb106oyWe6j5VYg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776700625; c=relaxed/simple; bh=TroU1k/1DWjqjPZeBCMsp1r8wA9lGBLFrQtXBaGh79U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gZ+8jtLJGFvnwhfShh27zAgHhi1+QKgM4pULcUtBlBki4PONRFeFPpgwUQbIhtuaDZYH9p0MWNL55gbCE1Y39x0KK0zLYaeGCWJB4OvphVTPmmx1Blis9XqfxauK1cs9DtU0yQWTPcqdX4IgwI6bdTFyYGnS69/d20dvXwzX3IA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=IIsBOxOH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="IIsBOxOH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A8D3C19425; Mon, 20 Apr 2026 15:57:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776700624; bh=TroU1k/1DWjqjPZeBCMsp1r8wA9lGBLFrQtXBaGh79U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IIsBOxOHHUrYUfVYR3TWyFoLnKcwdPvii/khb+CAHRK22KLdOYNiMuP4qN2SLGuMX 7wzepU5OyTHmzklxk8rwxu7w/Y3KI6L0Gq6vp94lLAOzun+tCw8QjZ306wj+WCt1+V 6TR+nw5n+4eQaRj9c7J2r9pR5WZDqlTBM3TeIbVI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Florian Westphal , Stefano Brivio , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 6.18 024/198] netfilter: nft_set_pipapo_avx2: dont return non-matching entry on expiry Date: Mon, 20 Apr 2026 17:40:03 +0200 Message-ID: <20260420153936.488116637@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420153935.605963767@linuxfoundation.org> References: <20260420153935.605963767@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Westphal [ Upstream commit d3c0037ffe1273fa1961e779ff6906234d6cf53c ] New test case fails unexpectedly when avx2 matching functions are used. The test first loads a ranomly generated pipapo set with 'ipv4 . port' key, i.e. nft -f foo. This works. Then, it reloads the set after a flush: (echo flush set t s; cat foo) | nft -f - This is expected to work, because its the same set after all and it was already loaded once. But with avx2, this fails: nft reports a clashing element. The reported clash is of following form: We successfully re-inserted a . b c . d Then we try to insert a . d avx2 finds the already existing a . d, which (due to 'flush set') is marked as invalid in the new generation. It skips the element and moves to next. Due to incorrect masking, the skip-step finds the next matching element *only considering the first field*, i.e. we return the already reinserted "a . b", even though the last field is different and the entry should not have been matched. No such error is reported for the generic c implementation (no avx2) or when the last field has to use the 'nft_pipapo_avx2_lookup_slow' fallback. Bisection points to 7711f4bb4b36 ("netfilter: nft_set_pipapo: fix range overlap detection") but that fix merely uncovers this bug. Before this commit, the wrong element is returned, but erronously reported as a full, identical duplicate. The root-cause is too early return in the avx2 match functions. When we process the last field, we should continue to process data until the entire input size has been consumed to make sure no stale bits remain in the map. Link: https://lore.kernel.org/netfilter-devel/20260321152506.037f68c0@elisabeth/ Signed-off-by: Florian Westphal Reviewed-by: Stefano Brivio Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nft_set_pipapo_avx2.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/net/netfilter/nft_set_pipapo_avx2.c b/net/netfilter/nft_set_pipapo_avx2.c index 7ff90325c97fa..6395982e4d95c 100644 --- a/net/netfilter/nft_set_pipapo_avx2.c +++ b/net/netfilter/nft_set_pipapo_avx2.c @@ -242,7 +242,7 @@ static int nft_pipapo_avx2_lookup_4b_2(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -319,7 +319,7 @@ static int nft_pipapo_avx2_lookup_4b_4(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -414,7 +414,7 @@ static int nft_pipapo_avx2_lookup_4b_8(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -505,7 +505,7 @@ static int nft_pipapo_avx2_lookup_4b_12(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -641,7 +641,7 @@ static int nft_pipapo_avx2_lookup_4b_32(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -699,7 +699,7 @@ static int nft_pipapo_avx2_lookup_8b_1(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -764,7 +764,7 @@ static int nft_pipapo_avx2_lookup_8b_2(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -839,7 +839,7 @@ static int nft_pipapo_avx2_lookup_8b_4(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -925,7 +925,7 @@ static int nft_pipapo_avx2_lookup_8b_6(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; @@ -1019,7 +1019,7 @@ static int nft_pipapo_avx2_lookup_8b_16(unsigned long *map, unsigned long *fill, b = nft_pipapo_avx2_refill(i_ul, &map[i_ul], fill, f->mt, last); if (last) - return b; + ret = b; if (unlikely(ret == -1)) ret = b / XSAVE_YMM_SIZE; -- 2.53.0