Re: CVE-2024-26602: sched/membarrier: reduce the ability to hammer on sys_membarrier

[Greg Kroah-Hartman]

On Sun, Feb 25, 2024 at 10:47:28AM +0100, Greg Kroah-Hartman wrote:
> On Sun, Feb 25, 2024 at 10:31:19AM +0100, Thorsten Leemhuis wrote:
> > On 24.02.24 15:57, Greg Kroah-Hartman wrote:
> > > Description
> > > ===========
> > > 
> > > In the Linux kernel, the following vulnerability has been resolved:
> > > 
> > > sched/membarrier: reduce the ability to hammer on sys_membarrier
> > > 
> > > On some systems, sys_membarrier can be very expensive, causing overall
> > > slowdowns for everything.  So put a lock on the path in order to
> > > serialize the accesses to prevent the ability for this to be called at
> > > too high of a frequency and saturate the machine.
> > > 
> > > The Linux kernel CVE team has assigned CVE-2024-26602 to this issue.
> > > 
> > > 
> > > Affected and fixed versions
> > > ===========================
> > > 
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 4.19.307 with commit 3cd139875e9a
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 5.4.269 with commit 2441a64070b8
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 5.10.210 with commit db896bbe4a9c
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 5.15.149 with commit 50fb4e17df31
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 6.1.79 with commit 24ec7504a08a
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 6.6.18 with commit b6a2a9cbb675
> > > 	Issue introduced in 4.14 with commit c5f58bd58f43 and fixed in 6.7.6 with commit c5b2063c65d0
> > >
> > > Please see [...]
> > Greg, JFYI, I noticed that this announcement did not refer to the fix in
> > mainline (944d5fe50f3f03 ("sched/membarrier: reduce the ability to
> > hammer on sys_membarrier")) while most of the others do that. I don't
> > care at all, just noticed this by chance and wanted to let you know in
> > case it's due to a bug in a script or something. I hope there is not a
> > good reason for that difference I just failed to spot... (if that's the
> > case: apologies in advance for the noise!).
> 
> The json entry will be updated when the commit shows up in a tagged
> release (i.e. the next -rc release), and then when the real release
> happens from Linus (i.e. 6.8), it will be updated then as well.

It is now updated on the cve.org website at:
	https://www.cve.org/CVERecord/?id=CVE-2024-26602
and in the cve git repo record as well:
	https://git.kernel.org/pub/scm/linux/security/vulns.git/diff/cve/published/2024/CVE-2024-26602.mbox

thanks,

greg k-h