[PATCH 5.10 054/406] netlabel: fix shift wrapping bug in netlbl_catmap_setlong()

Greg Kroah-Hartman
2023-09-17T19:22:35Z

From: Dmitry Mastykin <dmastykin@astralinux.ru>

[ Upstream commit b403643d154d15176b060b82f7fc605210033edd ]

There is a shift wrapping bug in this code on 32-bit architectures.
NETLBL_CATMAP_MAPTYPE is u64, bitmap is unsigned long.
Every second 32-bit word of catmap becomes corrupted.

Signed-off-by: Dmitry Mastykin <dmastykin@astralinux.ru>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/netlabel/netlabel_kapi.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c
index 91b35b7c80d82..96059c99b915e 100644
--- a/net/netlabel/netlabel_kapi.c
+++ b/net/netlabel/netlabel_kapi.c
@@ -857,7 +857,8 @@ int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap,

offset -= iter->startbit;
idx = offset / NETLBL_CATMAP_MAPSIZE;
- iter->bitmap[idx] |= bitmap << (offset % NETLBL_CATMAP_MAPSIZE);
+ iter->bitmap[idx] |= (NETLBL_CATMAP_MAPTYPE)bitmap
+ << (offset % NETLBL_CATMAP_MAPSIZE);

return 0;
}
--
2.40.1