Re: [PATCH][next] erofs: fix uninitialized variable i used in a while-loop

From: Gao Xiang
Date: Tue Apr 06 2021 - 19:54:18 EST


Hi Colin,

On Tue, Apr 06, 2021 at 05:27:18PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> The while-loop iterates until src is non-null or i is 3, however, the
> loop counter i is not intinitialied to zero, causing incorrect iteration
> counts. Fix this by initializing it to zero.
>
> Addresses-Coverity: ("Uninitialized scalar variable")
> Fixes: 1aa5f2e2feed ("erofs: support decompress big pcluster for lz4 backend")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Thank you very much for catching this! It looks good to me,
Reviewed-by: Gao Xiang <hsiangkao@xxxxxxxxxx>

(btw, may I fold this into the original patchset? since such big pcluster
patchset is just applied to for-next for further integration testing, and
the commit id is not stable yet..)

Thanks,
Gao Xiang

> ---
> fs/erofs/decompressor.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
> index fe46a9c34923..8687ff81406b 100644
> --- a/fs/erofs/decompressor.c
> +++ b/fs/erofs/decompressor.c
> @@ -154,6 +154,7 @@ static void *z_erofs_handle_inplace_io(struct z_erofs_decompress_req *rq,
> }
> kunmap_atomic(inpage);
> might_sleep();
> + i = 0;
> while (1) {
> src = vm_map_ram(rq->in, nrpages_in, -1);
> /* retry two more times (totally 3 times) */
> --
> 2.30.2
>