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Date:   Tue, 13 Apr 2021 10:25:01 -0700
From:   Boris Burkov <boris@bur.io>
To:     Khaled ROMDHANI <khaledromdhani216@gmail.com>
Cc:     clm@fb.com, josef@toxicpanda.com, dsterba@suse.com,
        linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org
Subject: Re: [PATCH-next] fs/btrfs: Fix uninitialized variable
Message-ID: <YHXT4kIrs28daRER@zen>
References: <20210413130604.11487-1-khaledromdhani216@gmail.com>
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In-Reply-To: <20210413130604.11487-1-khaledromdhani216@gmail.com>
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On Tue, Apr 13, 2021 at 02:06:04PM +0100, Khaled ROMDHANI wrote:
> The variable zone is not initialized. It
> may causes a failed assertion.
> 
> Addresses-Coverity: ("Uninitialized variables")
> 
> Signed-off-by: Khaled ROMDHANI <khaledromdhani216@gmail.com>

Reviewed-by: Boris Burkov <boris@bur.io>

> ---
>  fs/btrfs/zoned.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
> index eeb3ebe11d7a..ee15ab8dccb5 100644
> --- a/fs/btrfs/zoned.c
> +++ b/fs/btrfs/zoned.c
> @@ -136,7 +136,7 @@ static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zones,
>   */
>  static inline u32 sb_zone_number(int shift, int mirror)
>  {
> -	u64 zone;
> +	u64 zone = 0;
>  
>  	ASSERT(mirror < BTRFS_SUPER_MIRROR_MAX);

Thanks for the fix.

I assume this was dug up by coverity static analysis rather than hitting
it in a live system?

Since there is already an assert for the pre-condition 'mirror < max',
I feel like it would make sense to also add one for mirror > 0.

>  	switch (mirror) {
> -- 
> 2.17.1
>