From: Yufan Chen <[email protected]> In xen_9pfs_front_init(), parse the backend version list as comma-separated tokens with kstrtouint(). This improves error reporting and ensures strict token validation while explicitly requiring protocol version 1.
Signed-off-by: Yufan Chen <[email protected]> --- net/9p/trans_xen.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index 85b9ebfaa..f9fb2db7a 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -413,23 +413,29 @@ static int xen_9pfs_front_init(struct xenbus_device *dev) int ret, i; struct xenbus_transaction xbt; struct xen_9pfs_front_priv *priv; - char *versions, *v; - unsigned int max_rings, max_ring_order, len = 0; + char *versions, *v, *token; + bool version_1 = false; + unsigned int max_rings, max_ring_order, len = 0, version; versions = xenbus_read(XBT_NIL, dev->otherend, "versions", &len); if (IS_ERR(versions)) return PTR_ERR(versions); - for (v = versions; *v; v++) { - if (simple_strtoul(v, &v, 10) == 1) { - v = NULL; - break; + for (v = versions; (token = strsep(&v, ",")); ) { + if (!*token) + continue; + + ret = kstrtouint(token, 10, &version); + if (ret) { + kfree(versions); + return ret; } - } - if (v) { - kfree(versions); - return -EINVAL; + if (version == 1) + version_1 = true; } kfree(versions); + if (!version_1) + return -EINVAL; + max_rings = xenbus_read_unsigned(dev->otherend, "max-rings", 0); if (max_rings < XEN_9PFS_NUM_RINGS) return -EINVAL; -- 2.47.3
