From 8c71fa88f7778eb093ee22cba13a3813a82113ad Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 5 Dec 2017 17:38:43 +0300 Subject: xen/pvcalls: check for xenbus_read() errors Smatch complains that "len" is uninitialized if xenbus_read() fails so let's add some error handling. Signed-off-by: Dan Carpenter Reviewed-by: Juergen Gross Reviewed-by: Stefano Stabellini Signed-off-by: Boris Ostrovsky --- drivers/xen/pvcalls-front.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers') diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index 40caa92bff33..afa3f1b5d807 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -1128,6 +1128,8 @@ static int pvcalls_front_probe(struct xenbus_device *dev, } versions = xenbus_read(XBT_NIL, dev->otherend, "versions", &len); + if (IS_ERR(versions)) + return PTR_ERR(versions); if (!len) return -EINVAL; if (strcmp(versions, "1")) { -- cgit v1.2.3 From 1ab134ca3151c55b6fc606857e71d9adb4c355d1 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 5 Dec 2017 17:38:54 +0300 Subject: xen/pvcalls: Fix a check in pvcalls_front_remove() bedata->ref can't be less than zero because it's unsigned. This affects certain error paths in probe. We first set ->ref = -1 and then we set it to a valid value later. Fixes: 219681909913 ("xen/pvcalls: connect to the backend") Signed-off-by: Dan Carpenter Reviewed-by: Juergen Gross Reviewed-by: Stefano Stabellini Signed-off-by: Boris Ostrovsky --- drivers/xen/pvcalls-front.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index afa3f1b5d807..d1e1d8d2b9d5 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -1103,7 +1103,7 @@ static int pvcalls_front_remove(struct xenbus_device *dev) kfree(map); } } - if (bedata->ref >= 0) + if (bedata->ref != -1) gnttab_end_foreign_access(bedata->ref, 0, 0); kfree(bedata->ring.sring); kfree(bedata); -- cgit v1.2.3