[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAB9dFdvHsLsw7CMnB+4cgciWDSqVjuij4mH3TaXnHQB8sz5rHw@mail.gmail.com>
Date: Mon, 12 Jul 2021 11:20:47 -0300
From: Marc Dionne <marc.c.dionne@...il.com>
To: David Howells <dhowells@...hat.com>
Cc: linux-afs@...ts.infradead.org, Tom Rix <trix@...hat.com>,
linux-fsdevel@...r.kernel.org,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/3] afs: check function return
On Mon, Jul 12, 2021 at 9:57 AM David Howells <dhowells@...hat.com> wrote:
>
> From: Tom Rix <trix@...hat.com>
>
> Static analysis reports this problem
>
> write.c:773:29: warning: Assigned value is garbage or undefined
> mapping->writeback_index = next;
> ^ ~~~~
> The call to afs_writepages_region() can return without setting
> next. So check the function return before using next.
>
> Fixes: e87b03f5830e ("afs: Prepare for use of THPs")
> Signed-off-by: Tom Rix <trix@...hat.com>
> Signed-off-by: David Howells <dhowells@...hat.com>
> Link: https://lore.kernel.org/r/20210430155031.3287870-1-trix@redhat.com
> ---
>
> fs/afs/write.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/afs/write.c b/fs/afs/write.c
> index 3104b62c2082..2794147f82ff 100644
> --- a/fs/afs/write.c
> +++ b/fs/afs/write.c
> @@ -777,7 +777,7 @@ int afs_writepages(struct address_space *mapping,
> mapping->writeback_index = next / PAGE_SIZE;
Isn't there the same issue with the use of next here.
> } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) {
> ret = afs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next);
> - if (wbc->nr_to_write > 0)
> + if (wbc->nr_to_write > 0 && ret == 0)
> mapping->writeback_index = next;
Unrelated to this patch, but since next is a byte offset, should this
also divide by PAGE_SIZE as above.
> } else {
> ret = afs_writepages_region(mapping, wbc,
>
>
Marc
Powered by blists - more mailing lists