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Date: Wed, 22 Oct 2025 16:23:59 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: David Laight <david.laight.linux@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	LKML <linux-kernel@vger.kernel.org>,
	Christophe Leroy <christophe.leroy@csgroup.eu>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	kernel test robot <lkp@intel.com>,
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	linux-arm-kernel@lists.infradead.org, x86@kernel.org,
	Madhavan Srinivasan <maddy@linux.ibm.com>,
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	Nicholas Piggin <npiggin@gmail.com>, linuxppc-dev@lists.ozlabs.org,
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	linux-fsdevel@vger.kernel.org
Subject: Re: [patch V4 07/12] uaccess: Provide scoped user access regions
Message-ID: <20251022142359.GQ4067720@noisy.programming.kicks-ass.net>
References: <20251022102427.400699796@linutronix.de>
 <20251022103112.294959046@linutronix.de>
 <20251022152006.4d461c8b@pumpkin>
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In-Reply-To: <20251022152006.4d461c8b@pumpkin>

On Wed, Oct 22, 2025 at 03:20:06PM +0100, David Laight wrote:

> I think that 'feature' should be marked as a 'bug', consider code like:
> 	for (; len >= sizeof (*uaddr); uaddr++; len -= sizeof (*uaddr)) {
> 		scoped_user_read_access(uaddr, Efault) {
> 			int frag_len;
> 			unsafe_get_user(frag_len, &uaddr->len, Efault);
> 			if (!frag_len)
> 				break;
> 			...
> 		}
> 		...
> 	}
> 

All the scoped_* () things are for loops. break is a valid way to
terminate them.