[PATCH AUTOSEL 4.19 166/252] bpf: Return -EBADRQC for invalid map type in __bpf_tx_xdp_map

From: Sasha Levin
Date: Fri Feb 14 2020 - 11:16:19 EST


From: Li RongQing <lirongqing@xxxxxxxxx>

[ Upstream commit 0a29275b6300f39f78a87f2038bbfe5bdbaeca47 ]

A negative value should be returned if map->map_type is invalid
although that is impossible now, but if we run into such situation
in future, then xdpbuff could be leaked.

Daniel Borkmann suggested:

-EBADRQC should be returned to stay consistent with generic XDP
for the tracepoint output and not to be confused with -EOPNOTSUPP
from other locations like dev_map_enqueue() when ndo_xdp_xmit is
missing and such.

Suggested-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/bpf/1578618277-18085-1-git-send-email-lirongqing@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/core/filter.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index 9daf1a4118b51..40b3af05c883c 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3207,7 +3207,7 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
return err;
}
default:
- break;
+ return -EBADRQC;
}
return 0;
}
--
2.20.1