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=1794360659; b=H6w51shhOMD6vOu0TP6/gBrNa2FQpvYi/hXUFQA4UWUg3lOfcIHfiI68/CvJBhXzTcW1 WFetNKNQSVDE1GfNyQjPQvzrIbMZbxdfwULqg8CXp/LPzqSBIGg7fPIBa8Ik5lI3E72XB D6wWbzZLoDJo04py+EfthSkPAJv6NkCxoGKryB0pZ0s8+c9lSpRQ/UB3xYFVfVxhkrQVv cWibzJo8Wr7w+hfSfP9KF4Kc5UhSRjRhcv0fRvvJG2uXuSqFADsdsRbrzlwY+SlnopiQC AfHG2P6wRWdyB0Or+Iwev2I5dIlNcRHk2IxRugyZrYemgYBcJUqVPBYP0DDxMG/+Kaw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794360659; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=j3rDMSSsi8X7tG9zheqVZJ/0qpOILdzxmSnY5/XHtxc=; b=LnAOySBGFxbB6kAt5SkGnfTeIC+Yuqcnv7IJxLTrD8JkpGQUhNalKknskmQkyMycLxuz /lrvTVuFEQSSRG+nTqHTRixkYcRIuIB3vBZ09T1Dmmhyx4dsXKvwDpjJfPv4HA9VDFySB rEthXsI4ykMGJFNUfypRNa8AtKiH6jZ3W+QwqFck7URWlBgyKb/0MsRXVju4UIUdmlT/k CDln0p03aI1T3//7qZULTRazdVcRPnjB0glUVZt9KbTAwu7VXbxymBZe/1Pjo6dv0ZZOe 0lT2oA/1Cobg2iqFEYfmzrCxr8w2ek/17rekgmikAqtSc2rxTYchbzFDlvnDibzC6fQ== 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=Scm8sp1t; 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 2CA8B606A31C for ; Wed, 11 Nov 2026 01:30:58 +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=Scm8sp1t Received: by smtp.kernel.org (Postfix) with ESMTPSA id 292B71F0089F; Wed, 11 Nov 2026 01:30:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794360658; bh=j3rDMSSsi8X7tG9zheqVZJ/0qpOILdzxmSnY5/XHtxc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Scm8sp1tCb3kbB6SFvwlvYfAx2powxKWIOJSMq0JrMTd49Zj+zsLYYFr2JcQp7IS+ UJ3E+rnJSyGVeCoFrXfPmpYRLh2RhOi/ERYwcwjocLP7ikevvQZT28ENypGf8tGarS sE3pKULsQXub0J4y41PQRBxfBLLfAsCz24q43hwwnKPJmrR060//7RH++VXPQqJPAO nXvC2KSUTUar+Q2BEwlNh5+M4qqkSYMDFyL9NPhedbUjR3CBRWnPmqCHUw4hBTE+Uc i5FG6dejtFXKtHmJZdPmQvUwGkCDQbz0YEPMg1Q9XrR8rycArZvn2mYHNHgWpQU/S4 L3q7pRiVMAxuQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Konstantin Komarov , Weiming Shi , Xiang Mei , Sasha Levin Subject: [PATCH 6.18.y 1/3] fs/ntfs3: validate EA entry layout against ef->size in ntfs_read_ea Date: Tue, 10 Nov 2026 20:30:54 -0500 Message-ID: <20261111013025.390312-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261107051533-failed-6.18-351817226fbf@kernel.org> References: <20261107051533-failed-6.18-351817226fbf@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 0dbb410d51dfe..e246263aa3948 100644 --- a/fs/ntfs3/xattr.c +++ b/fs/ntfs3/xattr.c @@ -165,6 +165,8 @@ 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