On Tue, 26 May 2026 12:31:03 -0400
Steven Rostedt [off-list ref] wrote:

On Mon, 25 May 2026 11:42:41 +0100
David Laight [off-list ref] wrote:

quoted

quoted

quoted

 	error = security_task_prctl(option, arg2, arg3, arg4, arg5);

@@ -2601,16 +2601,16 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
 			error = -EINVAL;
 		break;
 	case PR_SET_NAME:
-		comm[sizeof(me->comm) - 1] = 0;
+		comm[TASK_COMM_LEN - 1] = 0;
 		if (strncpy_from_user(comm, (char __user *)arg2,
-				      sizeof(me->comm) - 1) < 0)
+				      TASK_COMM_LEN - 1) < 0)      

Nak - you can't do that.
You are reading data that the application doesn't expect you to read.    

Or have I got confused over the names...  

You may have gotten confused by names, as sizeof(me->comm) is the same as
TASK_COMM_LEN. Basically, the above doesn't change anything.

The name of the patch doesn't help:
	sched: Extend task command name to 64 bytes

If you want to catch/check all the uses I suspect that all the
occurrences of TASK_COMM_LEN need changing.
For clarity this one should probably be TASK_COMM_LEN_OLD.
(that might be problematic for the uapi headers)

-- David

-- Steve