[PATCH bpf-next v2] bpf: Fix 'dubious one-bit signed bitfield' warnings

From: Matthieu Baerts
Date: Mon Jul 11 2022 - 04:12:29 EST


Our CI[1] reported these warnings when using Sparse:

$ touch net/mptcp/bpf.c
$ make C=1 net/mptcp/bpf.o
net/mptcp/bpf.c: note: in included file:
include/linux/bpf_verifier.h:348:26: error: dubious one-bit signed bitfield
include/linux/bpf_verifier.h:349:29: error: dubious one-bit signed bitfield

Set them as 'unsigned' to avoid warnings.

[1] https://github.com/multipath-tcp/mptcp_net-next/actions/runs/2643588487

Fixes: 1ade23711971 ("bpf: Inline calls to bpf_loop when callback is known")
Signed-off-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx>
---

Notes:
v2: switch from 'bool' to 'unsigned int' (Yonghong Song)

include/linux/bpf_verifier.h | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 81b19669efba..2e3bad8640dc 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -345,10 +345,10 @@ struct bpf_verifier_state_list {
};

struct bpf_loop_inline_state {
- int initialized:1; /* set to true upon first entry */
- int fit_for_inline:1; /* true if callback function is the same
- * at each call and flags are always zero
- */
+ unsigned int initialized:1; /* set to true upon first entry */
+ unsigned int fit_for_inline:1; /* true if callback function is the same
+ * at each call and flags are always zero
+ */
u32 callback_subprogno; /* valid when fit_for_inline is true */
};

--
2.36.1