Re: CVE-2023-52437: Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Feb 20, 2024 at 07:34:08PM +0100, Greg Kroah-Hartman wrote:
> Description
> ===========
> 
> In the Linux kernel, the following vulnerability has been resolved:
> 
> Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"
> 
> This reverts commit 5e2cf333b7bd5d3e62595a44d598a254c697cd74.
> 
> That commit introduced the following race and can cause system hung.
> 
>  md_write_start:             raid5d:
>  // mddev->in_sync == 1
>  set "MD_SB_CHANGE_PENDING"
>                             // running before md_write_start wakeup it
>                              waiting "MD_SB_CHANGE_PENDING" cleared
>                              >>>>>>>>> hung
>  wakeup mddev->thread
>  ...
>  waiting "MD_SB_CHANGE_PENDING" cleared
>  >>>> hung, raid5d should clear this flag
>  but get hung by same flag.
> 
> The issue reverted commit fixing is fixed by last patch in a new way.
> 
> The Linux kernel CVE team has assigned CVE-2023-52437 to this issue.
> 
> 
> Affected and fixed versions
> ===========================
> 
> 	Issue introduced in 5.15.75 with commit 9e86dffd0b02 and fixed in 5.15.148 with commit 84c39986fe6d
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.1.74 with commit bed0acf330b2
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.1.75 with commit cfa468382858
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.6.13 with commit e16a0bbdb7e5
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.6.14 with commit aab69ef76970
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.7.1 with commit 0de40f76d567
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.7.2 with commit 87165c64fe1a
> 	Issue introduced in 6.1 with commit 5e2cf333b7bd and fixed in 6.8-rc1 with commit bed9e27baf52

As was pointed out, this list is obviously a mess and not correct for
what id cause the issue, and where it was fixed.  The tools we are using
here didn't handle the "Revert" knowledge very well.  I'll be issuing an
updated entry after this is fixed up, and will also update the json file
with cve.org

thanks,

greg k-h