[PATCH] netlabel: fix shift wrapping bug in netlbl_catmap_setlong()

Dmitry Mastykin dmastykin at astralinux.ru
Thu Jun 8 13:57:54 UTC 2023


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 at astralinux.ru>
---
 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 54c083003947..27511c90a26f 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;
 }
-- 
2.30.2



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