diff mbox series

[v2,1/2] wifi: ath12k: annotate skb of struct ath12k_ce_ring with __counted_by

Message ID 20241024112912.106104-1-dmantipov@yandex.ru (mailing list archive)
State New, archived
Headers show
Series [v2,1/2] wifi: ath12k: annotate skb of struct ath12k_ce_ring with __counted_by | expand

Commit Message

Dmitry Antipov Oct. 24, 2024, 11:29 a.m. UTC
According to 'ath12k_ce_alloc_ring()', annotate flexible array
member 'skb' of 'struct ath12k_ce_ring' with '__counted_by()'
to improve runtime bounds checking when CONFIG_UBSAN_BOUNDS is
enabled. Compile tested only.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v2: add related comment in ath12k_ce_alloc_ring()
---
 drivers/net/wireless/ath/ath12k/ce.c | 3 +++
 drivers/net/wireless/ath/ath12k/ce.h | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

Comments

Jeff Johnson Oct. 25, 2024, 12:53 a.m. UTC | #1
Please use get_maintainer.pl to make sure all the affected lists are notified.
Your ath11k/ath12k patches aren't hitting the ath11k/ath12k lists so they
aren't on my immediate radar.

Also note I'm not taking any of these __counted_by() changes without actually
either 1) testing with running code or 2) documenting all cases where the
array is accessed and cross-referencing when the counting member is updated.

I don't want to introduce any new warnings with your changes.
"If the isn't broken, don't fix it."

/jeff
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath12k/ce.c b/drivers/net/wireless/ath/ath12k/ce.c
index be0d669d31fc..23d984da2341 100644
--- a/drivers/net/wireless/ath/ath12k/ce.c
+++ b/drivers/net/wireless/ath/ath12k/ce.c
@@ -550,6 +550,9 @@  ath12k_ce_alloc_ring(struct ath12k_base *ab, int nentries, int desc_sz)
 	if (!ce_ring)
 		return ERR_PTR(-ENOMEM);
 
+	/* Note nentries should be set before populating skb[],
+	 * otherwise __counted_by() might raise false positives.
+	 */
 	ce_ring->nentries = nentries;
 	ce_ring->nentries_mask = nentries - 1;
 
diff --git a/drivers/net/wireless/ath/ath12k/ce.h b/drivers/net/wireless/ath/ath12k/ce.h
index 857bc5f9e946..6967e3891030 100644
--- a/drivers/net/wireless/ath/ath12k/ce.h
+++ b/drivers/net/wireless/ath/ath12k/ce.h
@@ -135,7 +135,7 @@  struct ath12k_ce_ring {
 	u32 hal_ring_id;
 
 	/* keep last */
-	struct sk_buff *skb[];
+	struct sk_buff *skb[] __counted_by(nentries);
 };
 
 struct ath12k_ce_pipe {