From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794362248; b=uBDbFiunDsABFeQ4qTYkSQ1+7Ig7wqGtw+O6ZV6QlY+/xC/DNt/Iq2RbEoIpbkkGreMH q33E55FgjYCzZgv8J9qK0z+9H9r9Rjat2UynpVJPP80xLwA2ThQQnwar4zSvpgaIJGLRq FXzwZbvun96Sg92KvaUpJesIuO7Xa+noju8hdTar7UXd4WumCI/HVEicZAsWYKYoYaUxU zaGR6MSsMq6Z6kVMS7iz/UhHcXq2/5AjiQKAgc9d2jLGgI7IL3lABVRTpoTKoPp82BUEg MLDhIcujGu6oRI+Zk2juR+j0nAlZ2Mx21pfxgZPKkyBz3oLKb0qObdkutdDkOzcYvgg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794362248; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=gxhrkjxl7/W7W7cDOdDg/PlAtP8upFZdjINyo9nqrhs=; b=TGTBZDI/VUxG/XuVoiOsb83Fc86T4hlWgsKoWnBG071KqxFwPGw2Sa5pI4eaTfMyDE5N F6Qn92T3wkk2Xht+iPGMqyycWIPgljvdTj8hNc+wZL2mTwXsGqddqpovrcDuk7TJWMKtl 5IJQlWT9BULPvohnkbW4PDi2lGQ2AaPfP5lG5Wsck73vEtE+ZbeODFgMOXhfG9yBiuGoI U4k3/f5GN3vOxd+Y6CuS6sh95PrcgcAW6N8148P0nHBKZlvulqbCZvoPzwrWH+/DXkzZB CaeLG5vDsxwfT+nCtWs5GOTFoCGu5SMIskNO9edZ9EKE+FY83iGvQhEiEKI7weHBKbQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=OlHry+56; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E29A4606A31C for ; Wed, 11 Nov 2026 01:57:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=OlHry+56 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3941A1F0089F; Wed, 11 Nov 2026 01:57:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794362247; bh=gxhrkjxl7/W7W7cDOdDg/PlAtP8upFZdjINyo9nqrhs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OlHry+56sJjrKFHOM513d+8+Xsg+yOnoHdgStYdcTXINGqYfuVxKcQmabtl3ThQ/n q/KPlGmRwJdCcVfq1dgeNrDt0VIxM/1hKddFauFwWJRicQOppOVCDtdeeG6jOArnQX IL7SVrQKlWAsQH7IYCAdbKaFHQGz+SOHNTuiPX1t7EVhdVG7EZdNYlRqPIAJVOi8V/ bEzwYAD/1H/hmRxjR02SI9COBxnbdNY50d+/ONNpGC8cWRksE3EYgyi2gCD6fZDBAS 4Qi40FuLOL+gwJF231FAYv2RK2JYLZrh4mtyOnAQvovPIS8QyZhC1dqIMm2C7es5Qt 8rwVx2E4csG/Q== From: Sasha Levin To: stable@vger.kernel.org Cc: Konstantin Komarov , Weiming Shi , Xiang Mei , Sasha Levin Subject: [PATCH 5.15.y 1/3] fs/ntfs3: validate EA entry layout against ef->size in ntfs_read_ea Date: Tue, 10 Nov 2026 20:57:23 -0500 Message-ID: <20261111015355.444686-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261107061313-failed-5.15-351817226fbf@kernel.org> References: <20261107061313-failed-5.15-351817226fbf@kernel.org> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Konstantin Komarov [ Upstream commit 01e56820ef52d14a5560fb7c0c6f2f75ef6f9393 ] In ntfs_read_ea(), the ef->size branch only checks that the declared entry size fits the remaining buffer; unlike the zero-size branch it never verifies that the entry's own name and value fit inside ef->size. A crafted image can thus present an in-bounds ef->size with an arbitrary elength, which find_ea()/ntfs_get_ea() later use as the memcpy length, reading past the allocation and leaking adjacent heap memory: BUG: KASAN: slab-out-of-bounds in ntfs_get_ea (fs/ntfs3/xattr.c:302) Read of size 65535 at addr ffff888010770b0f by task exploit/142 ... __asan_memcpy (mm/kasan/shadow.c:105) ntfs_get_ea (fs/ntfs3/xattr.c:302) ntfs_getxattr (fs/ntfs3/xattr.c:848) __vfs_getxattr (fs/xattr.c:446) vfs_getxattr (fs/xattr.c:479) do_getxattr (fs/xattr.c:808) filename_getxattr (fs/xattr.c:837) path_getxattrat (fs/xattr.c:876) do_syscall_64 (arch/x86/entry/syscall_64.c:94) ... The buggy address is located 15 bytes inside of allocated 20-byte region, cache kmalloc-32 Validate the name/value layout in the ef->size branch too, bounding it against ef->size, as the zero-size branch validates it against the buffer. Fixes: be71b5cba2e6 ("fs/ntfs3: Add attrib operations") Reported-by: Weiming Shi Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Xiang Mei [almaz.alexandrovich@paragon-software.com: remove duplicate check of need > ea_size] Signed-off-by: Konstantin Komarov Stable-dep-of: 351817226fbf ("fs/ntfs3: validate the EA value length in ntfs_read_ea()") Signed-off-by: Sasha Levin --- fs/ntfs3/xattr.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/ntfs3/xattr.c b/fs/ntfs3/xattr.c index c45133934c3ed..e05fd36cdd89a 100644 --- a/fs/ntfs3/xattr.c +++ b/fs/ntfs3/xattr.c @@ -164,6 +164,8 @@ static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea, /* ef->size must fit the list and cover the record. */ if (ea_size > bytes || ea_size < need) goto out1; + if (bytes < offsetof(struct EA_FULL, name)) + goto out1; continue; } -- 2.53.0