[PATCH AUTOSEL 4.19 11/81] mac80211: fix unaligned access in mesh table hash function

From: Sasha Levin
Date: Tue May 07 2019 - 02:01:51 EST


From: Felix Fietkau <nbd@xxxxxxxx>

[ Upstream commit 40586e3fc400c00c11151804dcdc93f8c831c808 ]

The pointer to the last four bytes of the address is not guaranteed to be
aligned, so we need to use __get_unaligned_cpu32 here

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/mac80211/mesh_pathtbl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index c3a7396fb955..49a90217622b 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -23,7 +23,7 @@ static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath);
static u32 mesh_table_hash(const void *addr, u32 len, u32 seed)
{
/* Use last four bytes of hw addr as hash index */
- return jhash_1word(*(u32 *)(addr+2), seed);
+ return jhash_1word(__get_unaligned_cpu32((u8 *)addr + 2), seed);
}

static const struct rhashtable_params mesh_rht_params = {
--
2.20.1