Commit 592ee43f authored Nov 13, 2018 by Colin Ian King Committed by Alexei Starovoitov Nov 16, 2018

bpf: fix null pointer dereference on pointer offload



Pointer offload is being null checked however the following statement
dereferences the potentially null pointer offload when assigning
offload->dev_state.  Fix this by only assigning it if offload is not
null.

Detected by CoverityScan, CID#1475437 ("Dereference after null check")

Fixes: 00db12c3 ("bpf: call verifier_prep from its callback in struct bpf_offload_dev")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

parent 29a9c10e

kernel/bpf/offload.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -130,9 +130,10 @@ int bpf_prog_offload_verifier_prep(struct bpf_prog *prog)

		down_read(&bpf_devs_lock);
		offload = prog->aux->offload;
		if (offload)
		if (offload) {
		ret = offload->offdev->ops->prepare(prog);
		offload->dev_state = !ret;
		}
		up_read(&bpf_devs_lock);

		return ret;

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