[bug] Crash with multiple file names

[bug] Crash with multiple file names

[Carl Henrik Lunde]

Hi!  fio crashed with this configuration.  I notice there are a
multiple variables counting the number of files, so I don't know which
one to use.  nr_files *seems* safe?

diff --git a/filesetup.c b/filesetup.c
index af23191..eb8774a 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -685,8 +685,8 @@ int add_file(struct thread_data *td, const char *fname)

        f->fd = -1;

-       if (td->files_size <= td->files_index) {
-               int new_size = td->o.nr_files;
+       if (td->files_size <= td->o.nr_files) {
+               int new_size = td->o.nr_files + 1;

                dprint(FD_FILE, "resize file array to %d files\n", new_size);


Test config:

[global]
directory=/media/ext4

[a]
filename=large-001:large-002:large-003:large-004:large-005:large-006
bs=1M
rw=read


x86_64, fio 1.25.1

-- 
mvh
Carl Henrik

Re: [bug] Crash with multiple file names

[Jens Axboe]

On Mon, Apr 20 2009, Carl Henrik Lunde wrote:
> Hi!  fio crashed with this configuration.  I notice there are a
> multiple variables counting the number of files, so I don't know which
> one to use.  nr_files *seems* safe?
> 
> diff --git a/filesetup.c b/filesetup.c
> index af23191..eb8774a 100644
> --- a/filesetup.c
> +++ b/filesetup.c
> @@ -685,8 +685,8 @@ int add_file(struct thread_data *td, const char *fname)
> 
>         f->fd = -1;
> 
> -       if (td->files_size <= td->files_index) {
> -               int new_size = td->o.nr_files;
> +       if (td->files_size <= td->o.nr_files) {
> +               int new_size = td->o.nr_files + 1;
> 
>                 dprint(FD_FILE, "resize file array to %d files\n", new_size);

Woops, that is indeed an off-by-one! I have added your patch, thanks.

Your reading of the code is correct. ->o.nr_files is the total number of
files.

-- 
Jens Axboe