[SCSI] sg: fix leak when dio setup fails
when the sg driver is unable to setup direct IO, free that scatter
gather list prior to falling back to indirect IO
Further to this thread started by Bryan Holty:
http://marc.theaimsgroup.com/?l=linux-scsi&m=114306885116728&w=2
Here is the reworked patch again. This time it has been
tested with a program provided by Bryan.
Signed-off-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index bfa86b3..b098942 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1799,8 +1799,10 @@
res = st_map_user_pages(schp->buffer, mx_sc_elems,
(unsigned long)hp->dxferp, dxfer_len,
(SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
- if (res <= 0)
+ if (res <= 0) {
+ sg_remove_scat(schp);
return 1;
+ }
schp->k_use_sg = res;
schp->dio_in_use = 1;
hp->info |= SG_INFO_DIRECT_IO;