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 5B4993955D2; Tue, 12 May 2026 17:57:19 +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=1778608639; cv=none; b=ptjlAvlKOa/T2o0JzvlbV9Pb3ryzRifPnhK9/5EA7RdR/X0TTLslsJ7eZMHL9s8vc+3a9rmjimzIbp7i5oGLFsshD2oeC54ZWeiJqYuQ51SZ7LrNezXIIYyyRTwMvbGoy8rDDzfFHomCXxPpiIbOzXnXY3XG+V087TSloM88nKY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778608639; c=relaxed/simple; bh=Kr/7rT/tPu+AakJBfh8RGSPSRr/eDom5mjmrmfbvBFA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UADBapdCW/UB+SCvRGdpNWbhLb3nSEKaYolPQiNAXtvVJE/q8ikGNISco6mIjfM51Fx7Q8cS9UHtqsUDP1r2VUKFGMlEKJ7RVQcHiwOC2jpe2fY1zbPiWIoSnL3vRNlDbK2D+V1Z2lXNkcIqhSu2YzKQEiIyIwlkdWIk2Y92vg0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=d8ByHXmJ; 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="d8ByHXmJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E66D2C2BCB0; Tue, 12 May 2026 17:57:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778608639; bh=Kr/7rT/tPu+AakJBfh8RGSPSRr/eDom5mjmrmfbvBFA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=d8ByHXmJaTfSmGu5YYULpBRDcKoRqIYPcedoNZ4IgA7zBUOxfHDKnVJwoAX+8hEPl IzGwcnzu7ShR4JvCbk7OhCT82RnMbT8hjGdR1XnCiudy1kJoyTerrUfuZLjComQdEf ktfTeFH8i//OmEK2gBPBBpXEUcBGKoSgPODU0KtA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Michael Bommarito , Jan Kara Subject: [PATCH 6.18 156/270] isofs: validate Rock Ridge CE continuation extent against volume size Date: Tue, 12 May 2026 19:39:17 +0200 Message-ID: <20260512173941.733203084@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260512173938.452574370@linuxfoundation.org> References: <20260512173938.452574370@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: Michael Bommarito commit a36d990f591320e9dd379ab30063ebfe91d47e1f upstream. rock_continue() reads rs->cont_extent verbatim from the Rock Ridge CE record and passes it to sb_bread() without checking that the block number is within the mounted ISO 9660 volume. commit e595447e177b ("[PATCH] rock.c: handle corrupted directories") added cont_offset and cont_size rejection for the CE continuation but did not validate the extent block number itself. commit f54e18f1b831 ("isofs: Fix infinite looping over CE entries") later capped the CE chain length at RR_MAX_CE_ENTRIES = 32 but again left the block number unchecked. With a crafted ISO mounted via udisks2 (desktop optical auto-mount) or via CAP_SYS_ADMIN mount, rs->cont_extent can therefore point at an out-of-range block or at blocks belonging to an adjacent filesystem on the same block device. sb_bread() on an out-of-range block returns NULL cleanly via the block layer EIO path, so there is no memory-safety violation. For in-range reads of adjacent- filesystem data, the CE buffer is parsed as Rock Ridge records and only the text of SL sub-records reaches userspace through readlink(), which makes the info-leak channel narrow and difficult to exploit; still, rejecting the malformed CE outright matches the rejection shape already present in the same function for cont_offset and cont_size. Add an ISOFS_SB(sb)->s_nzones bounds check to rock_continue() next to the existing offset/size rejection, printing the same corrupted-directory-entry notice. Fixes: f54e18f1b831 ("isofs: Fix infinite looping over CE entries") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito Link: https://patch.msgid.link/20260419212155.2169382-2-michael.bommarito@gmail.com Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/isofs/rock.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/fs/isofs/rock.c +++ b/fs/isofs/rock.c @@ -101,6 +101,15 @@ static int rock_continue(struct rock_sta goto out; } + if ((unsigned)rs->cont_extent >= ISOFS_SB(rs->inode->i_sb)->s_nzones) { + printk(KERN_NOTICE "rock: corrupted directory entry. " + "extent=%u out of volume (nzones=%lu)\n", + (unsigned)rs->cont_extent, + ISOFS_SB(rs->inode->i_sb)->s_nzones); + ret = -EIO; + goto out; + } + if (rs->cont_extent) { struct buffer_head *bh;