ACK/Cmnt: [PATCH 0/2] [SRU focal/linux-oem-5.6] CVE-2020-25656

[Stefan Bader]

On 22.02.21 20:39, Tim Gardner wrote:
> [Impact]
> A flaw was found in the Linux kernel. A use-after-free was found in the way the
> console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could
> use this flaw to get read memory access out of bounds. The highest threat from
> this vulnerability is to data confidentiality.
> 
> From the Ubuntu security team:
> It was discovered that the console keyboard driver in the Linux kernel contained
> a race condition. A local attacker could use this to expose sensitive information
> (kernel memory).
> 
> [Test Case]
> A test case is in the fix commit.
> 
> Patch 1/2 ('vt: keyboard, simplify vt_kdgkbsent') is required for the CVE fix
> commit Patch 2/2 ('vt: keyboard, extend func_buf_lock to readers').
> 
> [Potential regression]
> Both patches are clean upstream cherry-picks and have been released in multiple kernels.
> 
> 
As Thadeu already mentioned the first patch needs to be fixed up when applying.
Since there were already 2 try-again cases and this is "only" a missing part and
not randomly inventing new formats...

Acked-by: Stefan Bader <stefan.bader at canonical.com>

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <https://lists.ubuntu.com/archives/kernel-team/attachments/20210223/87c15fdd/attachment.sig>