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 B40F23537EF; Wed, 8 Apr 2026 18:28:29 +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=1775672909; cv=none; b=kb/R+5cJMUlEhsBANnshl/up+PrxjHivfuIZi+AFW9z0Rizu9jJjxIv9L2/pc00aVNP8ZNFdg9us1REWAD2Pb/+J3Y5HxyEq8Oe19qAOsfPD15PuVwCdQpb+fqQIopxZcaJg0pFe8YuQrq4ZLH8SalpJ9TsMaLO7sxp1aaqgt74= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775672909; c=relaxed/simple; bh=DOyHaR8UFlc5Cy18uHTvYXNBrN6eG+Z4nqnCypF1SOw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=O/yTxjioQwjZ7FHbIAAPM36o1zJ4d9Pnl+JSsOWcsMwOISkxuVkOobv79o82HbuzmciuIKSoR1oKbKcUxWWFj1jnK91s7bBVdbR8JxLcdb/avAAsJ5Knj3RfyVn2FyAFQU1YrhOKmyW0/H1h3qmO9LsuSiO35pWDxIbQrimgGoM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=W/VxJze/; 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="W/VxJze/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 45C2FC19421; Wed, 8 Apr 2026 18:28:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775672909; bh=DOyHaR8UFlc5Cy18uHTvYXNBrN6eG+Z4nqnCypF1SOw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=W/VxJze/3lel/rNclnSsjEpninxQWBBxvE4VYoKHKo0Nmr57Dp7tF5r1vekq3lyd/ YKIJ6fEOd+2qEqT4/grxygPDffL70fhG4fnh6QqE+FEyG9DTu8Y90HglaagZrrUMTg t+VdQfqAD4e3CvzobtzrvuAhHXb7ImvYvzomR+H0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mikulas Patocka , Herbert Xu , Sasha Levin Subject: [PATCH 6.18 027/277] crypto: deflate - fix spurious -ENOSPC Date: Wed, 8 Apr 2026 20:00:12 +0200 Message-ID: <20260408175934.866073838@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175933.836769063@linuxfoundation.org> References: <20260408175933.836769063@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org 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: Mikulas Patocka [ Upstream commit 6d89f743e57cb34e233a8217b394c7ee09abf225 ] The code in deflate_decompress_one may erroneously return -ENOSPC even if it didn't run out of output space. The error happens under this condition: - Suppose that there are two input pages, the compressed data fits into the first page and the zlib checksum is placed in the second page. - The code iterates over the first page, decompresses the data and fully fills the destination buffer, zlib_inflate returns Z_OK becuse zlib hasn't seen the checksum yet. - The outer do-while loop is iterated again, acomp_walk_next_src sets the input parameters to the second page containing the checksum. - We go into the inner do-while loop, execute "dcur = acomp_walk_next_dst(&walk);". "dcur" is zero, so we break out of the loop and return -ENOSPC, despite the fact that the decompressed data fit into the destination buffer. In order to fix this bug, this commit changes the logic when to report the -ENOSPC error. We report the error if the destination buffer is empty *and* if zlib_inflate didn't make any progress consuming the input buffer. If zlib_inflate consumes the trailing checksum, we see that it made progress and we will not return -ENOSPC. Fixes: 08cabc7d3c86 ("crypto: deflate - Convert to acomp") Signed-off-by: Mikulas Patocka Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- crypto/deflate.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/crypto/deflate.c b/crypto/deflate.c index 21404515dc77e..fd388dad5d60b 100644 --- a/crypto/deflate.c +++ b/crypto/deflate.c @@ -163,18 +163,21 @@ static int deflate_decompress_one(struct acomp_req *req, do { unsigned int dcur; + unsigned long avail_in; dcur = acomp_walk_next_dst(&walk); - if (!dcur) { - out_of_space = true; - break; - } stream->avail_out = dcur; stream->next_out = walk.dst.virt.addr; + avail_in = stream->avail_in; ret = zlib_inflate(stream, Z_NO_FLUSH); + if (!dcur && avail_in == stream->avail_in) { + out_of_space = true; + break; + } + dcur -= stream->avail_out; acomp_walk_done_dst(&walk, dcur); } while (ret == Z_OK && stream->avail_in); -- 2.53.0