s390/iucv: Fix vargs handling in iucv_alloc_device()

iucv_alloc_device() gets a format string and a varying number of
arguments. This is incorrectly forwarded by calling dev_set_name() with
the format string and a va_list, while dev_set_name() expects also a
varying number of arguments.

Symptoms:
Corrupted iucv device names, which can result in log messages like:
sysfs: cannot create duplicate filename '/devices/iucv/hvc_iucv1827699952'

Fixes: 4452e8ef8c36 ("s390/iucv: Provide iucv_alloc_device() / iucv_release_device()")
Link: https://bugzilla.suse.com/show_bug.cgi?id=1228425
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Thorsten Winkler <twinkler@linux.ibm.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://patch.msgid.link/20240821091337.3627068-1-wintera@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/iucv/iucv.c b/net/iucv/iucv.c
index 1e42e13ad24e36481e4039bf09f62d2229bb483a..d3e9efab7f4bd2a2251ab98d098d57d398fdb2a4 100644 (file)
--- a/net/iucv/iucv.c
+++ b/net/iucv/iucv.c
@@ -86,13 +86,15 @@ struct device *iucv_alloc_device(const struct attribute_group **attrs,
 {
        struct device *dev;
        va_list vargs;
+       char buf[20];
        int rc;
 
        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
        if (!dev)
                goto out_error;
        va_start(vargs, fmt);
-       rc = dev_set_name(dev, fmt, vargs);
+       vsnprintf(buf, sizeof(buf), fmt, vargs);
+       rc = dev_set_name(dev, "%s", buf);
        va_end(vargs);
        if (rc)
                goto out_error;