Re: [Qemu-devel] [PATCH] usb-mtp: use O_NOFOLLOW and O_CLOEXEC.

[P J P]

  Hello Gerd,

+-- On Thu, 13 Dec 2018, Markus Armbruster wrote --+
| Gerd Hoffmann <address@hidden> writes:
| > Open files and directories with O_NOFOLLOW to avoid symlinks attacks.
| > While being at it also add O_CLOEXEC.
| >
| > usb-mtp only handles regular files and directories and ignores
| > everything else, so users should not see a difference.
| >
| > Because qemu ignores symlinks carrying out an successfull symlink attack

   symlinks, carrying out a successful ...

| > requires swapping an existing file or directory below rootdir for a
| > symlink and winning the race against the inotify notification to qemu.
| >
| > Note that the impact of this bug is rather low when qemu is managed by
| > libvirt due to qemu running sandboxed, so there isn't much you can gain
| > access to that way.
| >
| > Fixes: CVE-2018-pjp-please-get-one
| 
| Ah, looks like we've run out of numbers.

Heh..:)

It's CVE-2018-16872. Thank you so much for the fix patch.

Thank you.
--
Prasad J Pandit / Red Hat Product Security Team
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