From bb3d2266747c617ecc001ae4ffb4f0a0312e49cb Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 30 Jan 2023 12:30:35 +0100 Subject: [PATCH] 9p/xen: fix version parsing [ Upstream commit 4bb5bf687e66d06713badbb6075bf56881a0f85e ] When connecting the Xen 9pfs frontend to the backend, the "versions" Xenstore entry written by the backend is parsed in a wrong way. The "versions" entry is defined to contain the versions supported by the backend separated by commas (e.g. "1,2"). Today only version "1" is defined. Unfortunately the frontend doesn't look for "1" being listed in the entry, but it is expecting the entry to have the value "1". This will result in failure as soon as the backend will support e.g. versions "1" and "2". Fix that by scanning the entry correctly. Link: https://lkml.kernel.org/r/20230130113036.7087-2-jgross@suse.com Fixes: e01cba69d3a9 ("xen/9pfs: connect to the backend") Signed-off-by: Juergen Gross Reviewed-by: Simon Horman Signed-off-by: Dominique Martinet Signed-off-by: Eric Van Hensbergen Signed-off-by: Sasha Levin --- net/9p/trans_xen.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index cf1b89ba522b4..80cc0289dd0d6 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -377,13 +377,19 @@ static int xen_9pfs_front_probe(struct xenbus_device *dev, int ret, i; struct xenbus_transaction xbt; struct xen_9pfs_front_priv *priv = NULL; - char *versions; + char *versions, *v; unsigned int max_rings, max_ring_order, len = 0; versions = xenbus_read(XBT_NIL, dev->otherend, "versions", &len); if (IS_ERR(versions)) return PTR_ERR(versions); - if (strcmp(versions, "1")) { + for (v = versions; *v; v++) { + if (simple_strtoul(v, &v, 10) == 1) { + v = NULL; + break; + } + } + if (v) { kfree(versions); return -EINVAL; } -- 2.39.5