Re: [PATCH resend] bsg: Fix sense buffer bug in SG_IO

From: Jens Axboe
Date: Tue Feb 03 2009 - 02:06:22 EST


On Tue, Feb 03 2009, FUJITA Tomonori wrote:
> On Tue, 03 Feb 2009 08:34:07 +0200
> Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote:
>
> >
> > When submitting requests via SG_IO, which does a sync io, a
> > bsg_command is not allocated. So an in-Kernel sense_buffer was not
> > set. However when calling blk_execute_rq() with no sense buffer
> > one is provided from the stack. Now bsg at blk_complete_sgv4_hdr_rq()
> > would check if rq->sense_len and a sense was requested by sg_io_v4
> > the rq->sense was copy_user() back, but by now it is already mangled
> > stack memory.
> >
> > I have fixed that by forcing a sense_buffer when calling bsg_map_hdr().
> > The bsg_command->sense is provided in the write/read path like before,
> > and on-the-stack buffer is provided when doing SG_IO.
> >
> > I have also fixed a dprintk message to print rq->errors in hex because
> > of the scsi bit-field use of this member. For other block devices it
> > does not matter anyway.
> >
> > Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx>
> > ---
> > block/bsg.c | 17 ++++++++++-------
> > 1 files changed, 10 insertions(+), 7 deletions(-)
>
> Acked-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
>
>
> I think I did this in the previous submission though.

Yeah, I also added it.

--
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/