syzbot reported :
BUG: KMSAN: uninit-value in rtnh_ok include/net/nexthop.h:11 [inline]
BUG: KMSAN: uninit-value in fib_count_nexthops net/ipv4/fib_semantics.c:469
[inline]
BUG: KMSAN: uninit-value in fib_create_info+0x554/0x8d20
net/ipv4/fib_semantics.c:1091
@remaining is an integer, coming from user space.
If it is negative we want rtnh_ok() to return false.
Fixes: 4e902c57417c ("[IPv4]: FIB configuration using struct fib_config")
Signed-off-by: Eric Dumazet <eduma...@google.com>
Reported-by: syzbot <syzkal...@googlegroups.com>
---
include/net/nexthop.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/net/nexthop.h b/include/net/nexthop.h
index
36bb794f5cd65cddc60139e7f84024f9f7a1a4cb..902ff382a6dcc6e3f0c1a9a244061e5a84264915
100644
--- a/include/net/nexthop.h
+++ b/include/net/nexthop.h
@@ -7,7 +7,7 @@
static inline int rtnh_ok(const struct rtnexthop *rtnh, int remaining)
{
- return remaining >= sizeof(*rtnh) &&
+ return remaining >= (int)sizeof(*rtnh) &&
rtnh->rtnh_len >= sizeof(*rtnh) &&
rtnh->rtnh_len <= remaining;
}
--
2.17.0.484.g0c8726318c-goog
