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 268F347F2DD for ; Thu, 13 Aug 2026 14:01:14 +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=1786629676; cv=none; b=TTBgCab6MJGZfz5GwTm5TSZX/ueudX6642BUjM07VYJwH7d95qUvDj1eLU1Nt3GHLVjNQ8DxaHlIM0WrLXx0QDeQ9XkEmlcd+8QSb/NrP08Svb/DzoA329gUxENGhGbsPQMhXD9vKjfcEeBmpdP6jpj8OhtQCzkMiWvSBIJlJyA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786629676; c=relaxed/simple; bh=wxjZCs9hYEpM9tlo8/Kh+pKrRnnfQtrFSBbQygpeHYQ=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=jxsYzrBRqpDOri7xPBO9v/rrtetzux3fd+XrUn7APj0fBO3R6p4NVj8jIBKFhxaiaaSrbc73VSPxOgxVBJ8WBOKI/Db6gJnc3tlFBWOhUzfrDNljSZZpMFAWg6TcJCnFOnxqtGvUkxqKxAGhlVhxA2tS0iBADH93d9WwVcJaHJU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qasnq0ge; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="qasnq0ge" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4082B1F000E9; Thu, 13 Aug 2026 14:01:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786629674; bh=bFE/Hct37g3gp/p/VbjKIam8PkWR1MB0sjJZC6/Dp+k=; h=Subject:To:Cc:From:Date; b=qasnq0geijWf/+vM87rCBfvII2jWDjDtKrqLAA8kUrJ41vekNIny50G9u7ferQzOs oNIf0siy3U7v/cVhVtjdbBVyrLETAxDgnczHf0MWqNkvZpmJKeRWCnZ9rYP+fwxSHc XCDU9SXmvg9wnMa6eCZJ+suz1ax5HhInsW6gvm+I= Subject: FAILED: patch "[PATCH] ima: fix out-of-bounds read in xattr_verify()" failed to apply to 5.10-stable tree To: locnnil0@gmail.com,zohar@linux.ibm.com Cc: From: Date: Thu, 13 Aug 2026 22:55:11 +0900 Message-ID: <2026081311-refutable-kiln-56fe@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 5ff232d31106f45ac87c3b64e1d35a0667777797 # git commit -s git send-email --to '' --in-reply-to '2026081311-refutable-kiln-56fe@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 5ff232d31106f45ac87c3b64e1d35a0667777797 Mon Sep 17 00:00:00 2001 From: Lincoln Wallace Date: Mon, 3 Aug 2026 10:50:21 -0300 Subject: [PATCH] ima: fix out-of-bounds read in xattr_verify() The digest-length check in xattr_verify() mixes int and size_t: if (xattr_len - sizeof(xattr_value->type) - hash_start >= iint->ima_hash->length) sizeof() yields size_t, so the usual arithmetic conversions promote the whole left-hand side to unsigned 64-bit before the subtraction runs. For a truncated xattr this underflows instead of going negative: a 1-byte IMA_XATTR_DIGEST_NG xattr (xattr_len == 1, hash_start == 1) turns "1 - 1 - 1" into SIZE_MAX, which is trivially >= ima_hash->length. The check then passes and the following memcmp() reads iint->ima_hash->length bytes starting past the end of the buffer vfs_getxattr_alloc() allocated for it. Nothing upstream clamps xattr_len back into a safe range first: ima_get_hash_algo() only special-cases xattr_len < 2 to pick a default algorithm, and evm_verifyxattr() returns INTEGRITY_UNKNOWN rather than failing when no HMAC key is loaded, so a truncated security.ima value reaches the length check as-is. Rewrite the comparison so every operand stays a signed int and no implicit conversion to size_t can occur. Fixes: 3ea7a56067e6 ("ima: provide hash algo info in the xattr") Cc: stable@vger.kernel.org Signed-off-by: Lincoln Wallace Signed-off-by: Mimi Zohar diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 18d0d9154317..ced2e131b061 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -274,8 +274,13 @@ static int xattr_verify(enum ima_hooks func, struct ima_iint_cache *iint, } else { set_bit(IMA_DIGSIG, &iint->atomic_flags); } - if (xattr_len - sizeof(xattr_value->type) - hash_start >= - iint->ima_hash->length) + /* + * Use addition, not subtraction: sizeof() forces unsigned + * math and a short xattr_len would wrap around, bypassing + * this bounds check. + */ + if (xattr_len >= (int)sizeof(xattr_value->type) + hash_start + + (int)iint->ima_hash->length) /* * xattr length may be longer. md5 hash in previous * version occupied 20 bytes in xattr, instead of 16