This reverts commit 942cb357ae7d9249088e3687ee6a00ed2745a0c7.
The io_uring PF_IO_WORKER threads no longer have PF_KTHREAD set, so no
need to special case them for credential checks.
Cc: Casey Schaufler <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
---
security/smack/smack_access.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index 7eabb448acab..efe2406a3960 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -688,10 +688,9 @@ bool smack_privileged_cred(int cap, const struct cred *cred)
bool smack_privileged(int cap)
{
/*
- * Kernel threads may not have credentials we can use.
- * The io_uring kernel threads do have reliable credentials.
+ * All kernel tasks are privileged
*/
- if ((current->flags & (PF_KTHREAD | PF_IO_WORKER)) == PF_KTHREAD)
+ if (unlikely(current->flags & PF_KTHREAD))
return true;
return smack_privileged_cred(cap, current_cred());
--
2.31.0
--
Jens Axboe
On 3/25/2021 5:42 PM, Jens Axboe wrote:
> This reverts commit 942cb357ae7d9249088e3687ee6a00ed2745a0c7.
>
> The io_uring PF_IO_WORKER threads no longer have PF_KTHREAD set, so no
> need to special case them for credential checks.
Could you cite the commit making that change?
I wouldn't want to see this change back-ported to a kernel
that doesn't have that change as well.
>
> Cc: Casey Schaufler <[email protected]>
> Signed-off-by: Jens Axboe <[email protected]>
> ---
> security/smack/smack_access.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
> index 7eabb448acab..efe2406a3960 100644
> --- a/security/smack/smack_access.c
> +++ b/security/smack/smack_access.c
> @@ -688,10 +688,9 @@ bool smack_privileged_cred(int cap, const struct cred *cred)
> bool smack_privileged(int cap)
> {
> /*
> - * Kernel threads may not have credentials we can use.
> - * The io_uring kernel threads do have reliable credentials.
> + * All kernel tasks are privileged
> */
> - if ((current->flags & (PF_KTHREAD | PF_IO_WORKER)) == PF_KTHREAD)
> + if (unlikely(current->flags & PF_KTHREAD))
> return true;
>
> return smack_privileged_cred(cap, current_cred());
On 3/26/21 10:00 AM, Casey Schaufler wrote:
> On 3/25/2021 5:42 PM, Jens Axboe wrote:
>> This reverts commit 942cb357ae7d9249088e3687ee6a00ed2745a0c7.
>>
>> The io_uring PF_IO_WORKER threads no longer have PF_KTHREAD set, so no
>> need to special case them for credential checks.
>
> Could you cite the commit making that change?
> I wouldn't want to see this change back-ported to a kernel
> that doesn't have that change as well.
This is strictly 5.12+. The change came about from:
commit 3bfe6106693b6b4ba175ad1f929c4660b8f59ca8
Author: Jens Axboe <[email protected]>
Date: Tue Feb 16 14:15:30 2021 -0700
io-wq: fork worker threads from original task
So don't backport it.
--
Jens Axboe
On 3/25/2021 5:42 PM, Jens Axboe wrote:
> This reverts commit 942cb357ae7d9249088e3687ee6a00ed2745a0c7.
>
> The io_uring PF_IO_WORKER threads no longer have PF_KTHREAD set, so no
> need to special case them for credential checks.
>
> Cc: Casey Schaufler <[email protected]>
> Signed-off-by: Jens Axboe <[email protected]>
I have added this to smack-next. Thank you.
> ---
> security/smack/smack_access.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
> index 7eabb448acab..efe2406a3960 100644
> --- a/security/smack/smack_access.c
> +++ b/security/smack/smack_access.c
> @@ -688,10 +688,9 @@ bool smack_privileged_cred(int cap, const struct cred *cred)
> bool smack_privileged(int cap)
> {
> /*
> - * Kernel threads may not have credentials we can use.
> - * The io_uring kernel threads do have reliable credentials.
> + * All kernel tasks are privileged
> */
> - if ((current->flags & (PF_KTHREAD | PF_IO_WORKER)) == PF_KTHREAD)
> + if (unlikely(current->flags & PF_KTHREAD))
> return true;
>
> return smack_privileged_cred(cap, current_cred());