From 7e897bb7be11983b0ef85be80e55ed6273540101 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Sun, 17 May 2020 10:44:31 +0300 Subject: [PATCH] thunderbolt: Check that both ports are reachable when allocating path Add sanity check that given src and dst ports are reachable through path walk before allocating a path. If they are not then bail out early. Signed-off-by: Mika Westerberg --- drivers/thunderbolt/path.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/thunderbolt/path.c b/drivers/thunderbolt/path.c index 77abb1fa80c0..854ff3412161 100644 --- a/drivers/thunderbolt/path.c +++ b/drivers/thunderbolt/path.c @@ -229,7 +229,7 @@ struct tb_path *tb_path_alloc(struct tb *tb, struct tb_port *src, int src_hopid, struct tb_port *dst, int dst_hopid, int link_nr, const char *name) { - struct tb_port *in_port, *out_port; + struct tb_port *in_port, *out_port, *first_port, *last_port; int in_hopid, out_hopid; struct tb_path *path; size_t num_hops; @@ -239,9 +239,20 @@ struct tb_path *tb_path_alloc(struct tb *tb, struct tb_port *src, int src_hopid, if (!path) return NULL; + first_port = last_port = NULL; i = 0; - tb_for_each_port_on_path(src, dst, in_port) + tb_for_each_port_on_path(src, dst, in_port) { + if (!first_port) + first_port = in_port; + last_port = in_port; i++; + } + + /* Check that src and dst are reachable */ + if (first_port != src || last_port != dst) { + kfree(path); + return NULL; + } /* Each hop takes two ports */ num_hops = i / 2;