net: ethernet: renesas: rswitch: Fix endless loop in error paths

Coverity reported that the error path in rswitch_gwca_queue_alloc_skb()
has an issue to cause endless loop. So, fix the issue by changing
variables' types from u32 to int. After changed the types,
rswitch_tx_free() should use rswitch_get_num_cur_queues() to
calculate number of current queues.

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1527147 ("Control flow issues")
Fixes: 3590918b5d ("net: ethernet: renesas: Add support for "Ethernet Switch"")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20221107081021.2955122-1-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Yoshihiro Shimoda 2022-11-07 17:10:21 +09:00 committed by Jakub Kicinski
parent 8e18be7610
commit 380f9acdf7
2 changed files with 12 additions and 11 deletions

View file

@ -219,9 +219,9 @@ static void rswitch_ack_data_irq(struct rswitch_private *priv, int index)
iowrite32(BIT(index % 32), priv->addr + offs);
}
static u32 rswitch_next_queue_index(struct rswitch_gwca_queue *gq, bool cur, u32 num)
static int rswitch_next_queue_index(struct rswitch_gwca_queue *gq, bool cur, int num)
{
u32 index = cur ? gq->cur : gq->dirty;
int index = cur ? gq->cur : gq->dirty;
if (index + num >= gq->ring_size)
index = (index + num) % gq->ring_size;
@ -231,7 +231,7 @@ static u32 rswitch_next_queue_index(struct rswitch_gwca_queue *gq, bool cur, u32
return index;
}
static u32 rswitch_get_num_cur_queues(struct rswitch_gwca_queue *gq)
static int rswitch_get_num_cur_queues(struct rswitch_gwca_queue *gq)
{
if (gq->cur >= gq->dirty)
return gq->cur - gq->dirty;
@ -250,9 +250,9 @@ static bool rswitch_is_queue_rxed(struct rswitch_gwca_queue *gq)
}
static int rswitch_gwca_queue_alloc_skb(struct rswitch_gwca_queue *gq,
u32 start_index, u32 num)
int start_index, int num)
{
u32 i, index;
int i, index;
for (i = 0; i < num; i++) {
index = (i + start_index) % gq->ring_size;
@ -410,12 +410,12 @@ static int rswitch_gwca_queue_format(struct net_device *ndev,
static int rswitch_gwca_queue_ts_fill(struct net_device *ndev,
struct rswitch_gwca_queue *gq,
u32 start_index, u32 num)
int start_index, int num)
{
struct rswitch_device *rdev = netdev_priv(ndev);
struct rswitch_ext_ts_desc *desc;
dma_addr_t dma_addr;
u32 i, index;
int i, index;
for (i = 0; i < num; i++) {
index = (i + start_index) % gq->ring_size;
@ -736,7 +736,8 @@ static int rswitch_tx_free(struct net_device *ndev, bool free_txed_only)
int free_num = 0;
int size;
for (; gq->cur - gq->dirty > 0; gq->dirty = rswitch_next_queue_index(gq, false, 1)) {
for (; rswitch_get_num_cur_queues(gq) > 0;
gq->dirty = rswitch_next_queue_index(gq, false, 1)) {
desc = &gq->ring[gq->dirty];
if (free_txed_only && (desc->desc.die_dt & DT_MASK) != DT_FEMPTY)
break;

View file

@ -908,9 +908,9 @@ struct rswitch_gwca_queue {
struct rswitch_ext_ts_desc *ts_ring;
};
dma_addr_t ring_dma;
u32 ring_size;
u32 cur;
u32 dirty;
int ring_size;
int cur;
int dirty;
struct sk_buff **skbs;
struct net_device *ndev; /* queue to ndev for irq */