2023-10-18 14:53:16

by Artem Chernyshev

Subject: [PATCH] nfp: bpf: offload: Check prog before dereference

In nfp_net_bpf_offload() it is possible to dereference a
NULL pointer.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Artem Chernyshev <[email protected]>
---
drivers/net/ethernet/netronome/nfp/bpf/offload.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/offload.c b/drivers/net/ethernet/netronome/nfp/bpf/offload.c
index 9d97cd281f18..925862f7b7d6 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/offload.c
@@ -598,8 +598,7 @@ int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
if (old_prog && !prog)
return nfp_net_bpf_stop(nn);

- err = nfp_net_bpf_load(nn, prog, extack);
- if (err)
+ if (prog && (err = nfp_net_bpf_load(nn, prog, extack)))
return err;

if (!old_prog)
--
2.37.3

2023-10-18 15:17:21

by Jakub Kicinski

Subject: Re: [PATCH] nfp: bpf: offload: Check prog before dereference

On Wed, 18 Oct 2023 17:52:44 +0300 Artem Chernyshev wrote:
> In nfp_net_bpf_offload() it is possible to dereference a
> NULL pointer.

And who would call this function with prog = NULL if old_prog
is also NULL, exactly?
--
pw-bot: cr