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 D54A2353A69 for ; Thu, 2 Jul 2026 15:11:03 +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=1783005065; cv=none; b=Q3CD2u5nbD/iC/PxFM3Xr1Sr7THwMwBEXoLR2QlJb3d7UGz4FtqCj6iyF4b/Wy+MHF7wBh+21PEPRdfO1yPPy2Tbza9YjzJjlWkaWqdk494TiT6+oZkoQQ2ZUFyLLTD5Pp7yvUQJcHo2dfEedkTxLrjYDGWSOs2Z91T93GrZJDk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783005065; c=relaxed/simple; bh=vAG03MBYvHJE5IgkzCs3C7ANbeDjY18pKYskMZSB7ro=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=guNm+beQt8WYPJbDbc48L0Lat60tG1m+tLPq7FYmmWr/X65f2Trg+mEWcN+rwu9L/3IS9GvOhuqEUHmi+RKs9iOFW0dkr7lAL2fozM2g7MRDBRFcpOmd5a1HzLpJtkPiWJEd5FWHYWKUj1V6x3SpFQ2c86IIPZPT8o1YhB/L0UU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W4/0WsgR; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="W4/0WsgR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2C461F000E9; Thu, 2 Jul 2026 15:11:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783005063; bh=5s/kPvOBQCRzXej8TG9V4RwhJt2LosTe+m5DDuDN8cQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=W4/0WsgRs6b/BnQcvrpqkicuBdgnRYwzAhAowueCNS4CC+P+QLtQ/DONg7VW5X+rk xoK80P0TtH44++bKiG5HJWGwLmMBbWJa7fbdddXT+xXRYQtOcJuCagsR8nCdsq5I91 Sk06q7yUt2FjBYw6IQdXnZVbNX8w9/xj6JV9S6tTj7MVE7VFF6l2xfS16IY6tJwON3 eUCHFk6GHJ9lBVSS7vI3RnNA5hWl5Ga46v5rqm0PCpfs312r+9/xuLK3NJNOf/p++q KydU2w+0giJdqCYHEGGZHE16PHGIJ776I1I1wtPhxZKIijmWYCO10/aP02aHGNWttH IGHl69cAYPMdA== From: Sasha Levin To: stable@vger.kernel.org Cc: Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 5.15.y 1/2] skmsg: convert struct sk_msg_sg::copy to a bitmap Date: Thu, 2 Jul 2026 11:11:00 -0400 Message-ID: <20260702151101.3512823-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026070245-deviation-chaffing-97e7@gregkh> References: <2026070245-deviation-chaffing-97e7@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit 5a8fb33e530512ee67a11b30f3451a4f030f4b01 ] We have plans for increasing MAX_SKB_FRAGS, but sk_msg_sg::copy is currently an unsigned long, limiting MAX_SKB_FRAGS to 30 on 32bit arches. Convert it to a bitmap, as Jakub suggested. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Stable-dep-of: 406e8a651a7b ("net: skmsg: preserve sg.copy across SG transforms") Signed-off-by: Sasha Levin --- include/linux/skmsg.h | 11 +++++------ net/core/filter.c | 4 ++-- 2 files changed, 7 insertions(+), 8 deletions(-) diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index 5d3e4d4d9438e2..7bc66fd7fc58c1 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -29,7 +29,7 @@ struct sk_msg_sg { u32 end; u32 size; u32 copybreak; - unsigned long copy; + DECLARE_BITMAP(copy, MAX_MSG_FRAGS + 2); /* The extra two elements: * 1) used for chaining the front and sections when the list becomes * partitioned (e.g. end < start). The crypto APIs require the @@ -38,7 +38,6 @@ struct sk_msg_sg { */ struct scatterlist data[MAX_MSG_FRAGS + 2]; }; -static_assert(BITS_PER_LONG >= NR_MSG_FRAG_IDS); /* UAPI in filter.c depends on struct sk_msg_sg being first element. */ struct sk_msg { @@ -236,7 +235,7 @@ static inline void sk_msg_compute_data_pointers(struct sk_msg *msg) { struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start); - if (test_bit(msg->sg.start, &msg->sg.copy)) { + if (test_bit(msg->sg.start, msg->sg.copy)) { msg->data = NULL; msg->data_end = NULL; } else { @@ -255,7 +254,7 @@ static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page, sg_set_page(sge, page, len, offset); sg_unmark_end(sge); - __set_bit(msg->sg.end, &msg->sg.copy); + __set_bit(msg->sg.end, msg->sg.copy); msg->sg.size += len; sk_msg_iter_next(msg, end); } @@ -264,9 +263,9 @@ static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state) { do { if (copy_state) - __set_bit(i, &msg->sg.copy); + __set_bit(i, msg->sg.copy); else - __clear_bit(i, &msg->sg.copy); + __clear_bit(i, msg->sg.copy); sk_msg_iter_var_next(i); if (i == msg->sg.end) break; diff --git a/net/core/filter.c b/net/core/filter.c index 6a1210abe4625e..5874ecb192098c 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2660,7 +2660,7 @@ BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start, * account for the headroom. */ bytes_sg_total = start - offset + bytes; - if (!test_bit(i, &msg->sg.copy) && bytes_sg_total <= len) + if (!test_bit(i, msg->sg.copy) && bytes_sg_total <= len) goto out; /* At this point we need to linearize multiple scatterlist @@ -2883,7 +2883,7 @@ BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start, /* Place newly allocated data buffer */ sk_mem_charge(msg->sk, len); msg->sg.size += len; - __clear_bit(new, &msg->sg.copy); + __clear_bit(new, msg->sg.copy); sg_set_page(&msg->sg.data[new], page, len + copy, 0); if (rsge.length) { get_page(sg_page(&rsge)); -- 2.53.0