Re: [PATCH] interface: fix udev_device_get_sysattr_value return value check
On Fri, Sep 08, 2023 at 13:06:43 +0300, Dmitry Frolov wrote:
Reviewing the code I found that return value of function
udev_device_get_sysattr_value() is dereferenced without a check.
udev_device_get_sysattr_value() may return NULL by number of reasons.
Signed-off-by: Dmitry Frolov <frolov(a)swemel.ru>
---
src/interface/interface_backend_udev.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/src/interface/interface_backend_udev.c
b/src/interface/interface_backend_udev.c
index a0485ddd21..c820b3ccdf 100644
--- a/src/interface/interface_backend_udev.c
+++ b/src/interface/interface_backend_udev.c
@@ -355,10 +355,11 @@ udevConnectListAllInterfaces(virConnectPtr conn,
g_autoptr(virInterfaceDef) def = NULL;
path = udev_list_entry_get_name(dev_entry);
- dev = udev_device_new_from_syspath(udev, path);
+ if (!(dev = udev_device_new_from_syspath(udev, path)))
+ continue;
IMO this warants at least a VIR_DEBUG stating that the returned
'dev' struct is NULL and thus we're skipping a whole interface.
name = udev_device_get_sysname(dev);
This is also documented as returning NULL on error, but virGetInterface
actually checks it before use.
macaddr = udev_device_get_sysattr_value(dev,
"address");
- status = STREQ(udev_device_get_sysattr_value(dev, "operstate"),
"up");
+ status = STREQ(NULLSTR(udev_device_get_sysattr_value(dev,
"operstate")), "up");
For comparing strings which can be NULL we have STREQ_NULLABLE and
STRNEQ_NULLABLE.