CVE-2024-47725: dm-verity: restart or panic on an I/O error

CVE-2024-47725: dm-verity: restart or panic on an I/O error

[Greg Kroah-Hartman]

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

dm-verity: restart or panic on an I/O error

Maxim Suhanov reported that dm-verity doesn't crash if an I/O error
happens. In theory, this could be used to subvert security, because an
attacker can create sectors that return error with the Write Uncorrectable
command. Some programs may misbehave if they have to deal with EIO.

This commit fixes dm-verity, so that if "panic_on_corruption" or
"restart_on_corruption" was specified and an I/O error happens, the
machine will panic or restart.

This commit also changes kernel_restart to emergency_restart -
kernel_restart calls reboot notifiers and these reboot notifiers may wait
for the bio that failed. emergency_restart doesn't call the notifiers.

The Linux kernel CVE team has assigned CVE-2024-47725 to this issue.


Affected and fixed versions
===========================

	Fixed in 6.6.54 with commit cada2646b748
	Fixed in 6.10.13 with commit b332bcca5914
	Fixed in 6.11.2 with commit 338b32a232bb
	Fixed in 6.12-rc1 with commit e6a3531dd542

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-47725
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/md/dm-verity-target.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/cada2646b7483cce370eb3b046659df31d9d34d1
	https://git.kernel.org/stable/c/b332bcca59143cfdd000957f8b78c28dd2ac1da4
	https://git.kernel.org/stable/c/338b32a232bbee39e52dd1486cbc0c9f458d4d69
	https://git.kernel.org/stable/c/e6a3531dd542cb127c8de32ab1e54a48ae19962b

Re: CVE-2024-47725: dm-verity: restart or panic on an I/O error

[Li Lingfeng]

Hi

I noticed that the fix patch for this CVE has been reverted by commit
462763212dd7("Revert: "dm-verity: restart or panic on an I/O error"").
So should this CVE also be rejected?

Thanks

在 2024/10/21 20:16, Greg Kroah-Hartman 写道:
> Description
> ===========
>
> In the Linux kernel, the following vulnerability has been resolved:
>
> dm-verity: restart or panic on an I/O error
>
> Maxim Suhanov reported that dm-verity doesn't crash if an I/O error
> happens. In theory, this could be used to subvert security, because an
> attacker can create sectors that return error with the Write Uncorrectable
> command. Some programs may misbehave if they have to deal with EIO.
>
> This commit fixes dm-verity, so that if "panic_on_corruption" or
> "restart_on_corruption" was specified and an I/O error happens, the
> machine will panic or restart.
>
> This commit also changes kernel_restart to emergency_restart -
> kernel_restart calls reboot notifiers and these reboot notifiers may wait
> for the bio that failed. emergency_restart doesn't call the notifiers.
>
> The Linux kernel CVE team has assigned CVE-2024-47725 to this issue.
>
>
> Affected and fixed versions
> ===========================
>
> 	Fixed in 6.6.54 with commit cada2646b748
> 	Fixed in 6.10.13 with commit b332bcca5914
> 	Fixed in 6.11.2 with commit 338b32a232bb
> 	Fixed in 6.12-rc1 with commit e6a3531dd542
>
> Please see https://www.kernel.org for a full list of currently supported
> kernel versions by the kernel community.
>
> Unaffected versions might change over time as fixes are backported to
> older supported kernel versions.  The official CVE entry at
> 	https://cve.org/CVERecord/?id=CVE-2024-47725
> will be updated if fixes are backported, please check that for the most
> up to date information about this issue.
>
>
> Affected files
> ==============
>
> The file(s) affected by this issue are:
> 	drivers/md/dm-verity-target.c
>
>
> Mitigation
> ==========
>
> The Linux kernel CVE team recommends that you update to the latest
> stable kernel version for this, and many other bugfixes.  Individual
> changes are never tested alone, but rather are part of a larger kernel
> release.  Cherry-picking individual commits is not recommended or
> supported by the Linux kernel community at all.  If however, updating to
> the latest release is impossible, the individual changes to resolve this
> issue can be found at these commits:
> 	https://git.kernel.org/stable/c/cada2646b7483cce370eb3b046659df31d9d34d1
> 	https://git.kernel.org/stable/c/b332bcca59143cfdd000957f8b78c28dd2ac1da4
> 	https://git.kernel.org/stable/c/338b32a232bbee39e52dd1486cbc0c9f458d4d69
> 	https://git.kernel.org/stable/c/e6a3531dd542cb127c8de32ab1e54a48ae19962b

Re: CVE-2024-47725: dm-verity: restart or panic on an I/O error

[Greg Kroah-Hartman]

On Wed, Oct 23, 2024 at 09:37:26AM +0800, Li Lingfeng wrote:
> Hi
> 
> I noticed that the fix patch for this CVE has been reverted by commit
> 462763212dd7("Revert: "dm-verity: restart or panic on an I/O error"").
> So should this CVE also be rejected?

Yes it should, as the revert happened in the same releases.  I'll go do
that now, thanks for the review!

greg k-h