linux-kernel - Re: mainline build failure due to 6c77676645ad ("iov_iter: Fix iter_xarray_get_pages{,

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <1075696.1655111958@warthog.procyon.org.uk>
Date:   Mon, 13 Jun 2022 10:19:18 +0100
From:   David Howells <dhowells@...hat.com>
To:     Al Viro <viro@...iv.linux.org.uk>
Cc:     dhowells@...hat.com, Sudip Mukherjee <sudipm.mukherjee@...il.com>,
        Dominique Martinet <asmadeus@...ewreck.org>,
        Mike Marshall <hubcap@...ibond.com>,
        Gao Xiang <xiang@...nel.org>, linux-afs@...ts.infradead.org,
        v9fs-developer@...ts.sourceforge.net, devel@...ts.orangefs.org,
        linux-erofs@...ts.ozlabs.org, linux-cachefs@...hat.com,
        linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
        Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: mainline build failure due to 6c77676645ad ("iov_iter: Fix iter_xarray_get_pages{,_alloc}()")

Al Viro <viro@...iv.linux.org.uk> wrote:

> The reason we can't overflow on multiplication there, BTW, is that we have
> nr <= count, and count has come from weirdly open-coded
> 	DIV_ROUND_UP(size + offset, PAGE_SIZE)
> IMO we'd better make it explicit, so how about the following:
> 
> Signed-off-by: Al Viro <viro@...iv.linux.org.uk>

It seems reasonable.

Reviewed-by: David Howells <dhowells@...hat.com>