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From: David Howells <dhowells@redhat.com>
In-Reply-To: <20211204220350.633811-1-arnd@kernel.org>
References: <20211204220350.633811-1-arnd@kernel.org>
To: Arnd Bergmann <arnd@kernel.org>
Cc: dhowells@redhat.com, Arnd Bergmann <arnd@arndb.de>,
    Nathan Chancellor <nathan@kernel.org>,
    Nick Desaulniers <ndesaulniers@google.com>,
    Jeff Layton <jlayton@kernel.org>, linux-cachefs@redhat.com,
    linux-kernel@vger.kernel.org, llvm@lists.linux.dev
Subject: Re: [PATCH] cachefiles: fix __cachefiles_prepare_write() error handling
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Date: Tue, 07 Dec 2021 17:02:20 +0000
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X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16

Arnd Bergmann <arnd@kernel.org> wrote:

>  	pos = cachefiles_inject_remove_error();
> -	if (pos == 0)
> -		ret = vfs_fallocate(file, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
> -				    *_start, *_len);
> +	if (pos != 0)
> +		return 0;
> +
> +	ret = vfs_fallocate(file, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
> +			    *_start, *_len);
>  	if (ret < 0) {

The right fix is to use "ret" rather than "pos".  I've fixed this already on
my fscache-rewrite branch.  Hopefully I'll be able to push that over to my
next branch shortly.

David