Sorry for that, I will send today a fix that reduce the need for the internal(index) check.
-----Original Message-----
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Sent: Tuesday, November 9, 2021 1:42 PM
To: Saeed Mahameed <saeedm@xxxxxxxxxx>; Ben Ben Ishay <benishay@xxxxxxxxxx>
Cc: Leon Romanovsky <leon@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Tariq Toukan <tariqt@xxxxxxxxxx>; linux-rdma@xxxxxxxxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx
Subject: [PATCH net-next] net/mlx5e: Fix signedness bugs in mlx5e_build_shampo_hd_umr()
External email: Use caution opening links or attachments
The error handling has a couple forever loops which will lead to a crash. Unsigned values are always greater or equal to zero.
Fixes: 64509b052525 ("net/mlx5e: Add data path for SHAMPO feature")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 96967b0a2441..8cd120666b2d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -543,13 +543,14 @@ static int mlx5e_build_shampo_hd_umr(struct mlx5e_rq *rq,
u16 klm_entries, u16 index) {
struct mlx5e_shampo_hd *shampo = rq->mpwqe.shampo;
- u16 entries, pi, i, header_offset, err, wqe_bbs, new_entries;
+ u16 entries, pi, header_offset, err, wqe_bbs, new_entries;
u32 lkey = rq->mdev->mlx5e_res.hw_objs.mkey;
struct page *page = shampo->last_page;
u64 addr = shampo->last_addr;
struct mlx5e_dma_info *dma_info;
struct mlx5e_umr_wqe *umr_wqe;
int headroom;
+ int i;
headroom = rq->buff.headroom;
new_entries = klm_entries - (shampo->pi & (MLX5_UMR_KLM_ALIGNMENT - 1)); @@ -601,8 +602,11 @@ static int mlx5e_build_shampo_hd_umr(struct mlx5e_rq *rq,
err_unmap:
while (--i >= 0) {
- if (--index < 0)
+ if (index == 0)
index = shampo->hd_per_wq - 1;
+ else
+ index--;
+
dma_info = &shampo->info[index];
if (!(i & (MLX5E_SHAMPO_WQ_HEADER_PER_PAGE - 1))) {
dma_info->addr = ALIGN_DOWN(dma_info->addr, PAGE_SIZE);
--
2.20.1
