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From: Al Viro <viro@zeniv.linux.org.uk>
To: "Maíra Canal" <maira.canal@usp.br>
Cc: gregkh@linuxfoundation.org, tj@kernel.org, nathan@kernel.org,
	ndesaulniers@google.com, willy@infradead.org,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	llvm@lists.linux.dev
Subject: Re: [PATCH v3] seq_file: fix NULL pointer arithmetic warning
Date: Tue, 1 Feb 2022 16:32:27 +0000	[thread overview]
Message-ID: <Yflgm3kv1059tIDH@zeniv-ca.linux.org.uk> (raw)
In-Reply-To: <Yfgo8p6Vk+h4+YHY@fedora>

On Mon, Jan 31, 2022 at 03:22:42PM -0300, Maíra Canal wrote:
> Implement conditional logic in order to replace NULL pointer arithmetic.
> 
> The use of NULL pointer arithmetic was pointed out by clang with the
> following warning:
> 
> fs/kernfs/file.c:128:15: warning: performing pointer arithmetic on a
> null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>                 return NULL + !*ppos;
>                        ~~~~ ^
> fs/seq_file.c:559:14: warning: performing pointer arithmetic on a
> null pointer has undefined behavior [-Wnull-pointer-arithmetic]
>         return NULL + (*pos == 0);
> 
> Signed-off-by: Maíra Canal <maira.canal@usp.br>
> ---
> V1 -> V2:
> - Use SEQ_START_TOKEN instead of open-coding it
> - kernfs_seq_start call single_start instead of open-coding it
> V2 -> V3:
> - Remove the EXPORT of the single_start symbol

Applied.

      parent reply	other threads:[~2022-02-01 16:32 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-31 18:22 [PATCH v3] seq_file: fix NULL pointer arithmetic warning Maíra Canal
2022-02-01 16:26 ` Nathan Chancellor
2022-02-01 16:30 ` Matthew Wilcox
2022-02-01 16:32 ` Al Viro [this message]

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