linux-kernel - /proc/bus/pci IOCTL breakage

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-next>] [day] [month] [year] [list]

Message-Id: <20070726.190751.66179795.davem@davemloft.net>
Date:	Thu, 26 Jul 2007 19:07:51 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	linux-kernel@...r.kernel.org
CC:	adobriyan@...ru
Subject: /proc/bus/pci IOCTL breakage

This change:

commit 786d7e1612f0b0adb6046f19b906609e4fe8b1ba
Author: Alexey Dobriyan <adobriyan@...ru>
Date:   Sun Jul 15 23:39:00 2007 -0700

    Fix rmmod/read/write races in /proc entries

Broke ioctl() on /proc/bus/pci/* files for COMPAT platforms.

proc_fops->ioctl() is defined for these PCI device files, and the
COMPAT ioctl is handled via fs/compat_ioctl.c's entries, which makes
it just call the ->ioctl() handler directly.

proc_fops->compat_ioctl is NULL for these files, it isn't needed.

This used to work because we used to jump right to the de->proc_fops,
but now we have these wrappers and proc_reg_compat_ioctl is what
gets called and since proc_fops->compat_ioctl is NULL we return
ENOTTY instead of calling proc_fops->ioctl().

Two ways to fix:

1) Make the PROC wrapper call ->unlocked_ioctl() or ->ioctl()
   as a fallback of ->compat_ioctl is NULL.

2) Make proc_bus_pci_operations provide a .compat_ioctl method,
   but then we'll need to audit the entire tree for cases like
   this and make the same fix.

Because it's easier to validate that all cases are covered,
I think #1 is the preferred fix.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/