[sheepdog] [PATCH] bs_sheepdog.c: ensure that vdi names and tag names are null-terminated

[Hitoshi Mitake]

At Mon,  9 Dec 2013 14:00:41 +0900,
Ryusuke Konishi wrote:
> 
> In the current sheepdog driver, tag names and vdi names are truncated
> to 256 bytes if they are longer than the size.
> 
> The request data will not be null-terminated if those names are
> truncated to the maximum byte size.
> 
> This implementation causes the following two issues with sheepdog:
> 
>  1) Since CLI of sheepdog (i.e. dog command) truncates tag names and
>     vdi names to 255 bytes to ensure that string buffers are
>     null-terminated, vdi lookup function of sheep daemon can fail for
>     long vdi names or long tag names due to this difference of buffer
>     termination.
> 
>  2) The absence of a null byte causes potential buffer overrun issue
>     with the sheep daemon even though we are trying to fix this sort
>     of dangerous implementation.
> 
> This patch ensures that tag names and vdi names set to the request
> buffer are both null terminated and fixes these issues.
> 
> Signed-off-by: Ryusuke Konishi <konishi.ryusuke at lab.ntt.co.jp>
> Cc: Hitoshi Mitake <mitake.hitoshi at lab.ntt.co.jp>
> ---
>  usr/bs_sheepdog.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Looks good to me, thanks for your fix.

Reviewed-by: Hitoshi Mitake <mitake.hitoshi at lab.ntt.co.jp>

Thanks,
Hitoshi