[PULL v2 2/6] vfio-ccw: Fix memory leak and don't call cp_free in cp_init

Cornelia Huck
2019-07-17T09:44:01Z

We don't set cp->initialized to true so calling cp_free
will just return and not do anything.

Also fix a memory leak where we fail to free a ccwchain
on an error.

Fixes: 812271b910 ("s390/cio: Squash cp_free() and cp_unpin_free()")
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <3173c4216f4555d9765eb6e4922534982bc820e4.1562854091.git.alifm@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
---
drivers/s390/cio/vfio_ccw_cp.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
index 46967c664c0f..e4e8724eddaa 100644
--- a/drivers/s390/cio/vfio_ccw_cp.c
+++ b/drivers/s390/cio/vfio_ccw_cp.c
@@ -421,7 +421,7 @@ static int ccwchain_loop_tic(struct ccwchain *chain,
static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp)
{
struct ccwchain *chain;
- int len;
+ int len, ret;

/* Copy 2K (the most we support today) of possible CCWs */
len = copy_from_iova(cp->mdev, cp->guest_cp, cda,
@@ -448,7 +448,12 @@ static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp)
memcpy(chain->ch_ccw, cp->guest_cp, len * sizeof(struct ccw1));

/* Loop for tics on this new chain. */
- return ccwchain_loop_tic(chain, cp);
+ ret = ccwchain_loop_tic(chain, cp);
+
+ if (ret)
+ ccwchain_free(chain);
+
+ return ret;
}

/* Loop for TICs. */
@@ -642,8 +647,6 @@ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb)

/* Build a ccwchain for the first CCW segment */
ret = ccwchain_handle_ccw(orb->cmd.cpa, cp);
- if (ret)
- cp_free(cp);

if (!ret) {
cp->initialized = true;
--
2.20.1