The members in the LLI list is released in an incorrect way. Read and
store the next member before releasing it to avoid accessing the freed
memory.
Fixes: a90e173f3faf ("dmaengine: sun6i: Add cyclic capability")
Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
---
drivers/dma/sun6i-dma.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)
diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c
index 06cd7f867f7c..096aad7e75bb 100644
--- a/drivers/dma/sun6i-dma.c
+++ b/drivers/dma/sun6i-dma.c
@@ -687,7 +687,7 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg(
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct dma_slave_config *sconfig = &vchan->cfg;
- struct sun6i_dma_lli *v_lli, *prev = NULL;
+ struct sun6i_dma_lli *v_lli, *next, *prev = NULL;
struct sun6i_desc *txd;
struct scatterlist *sg;
dma_addr_t p_lli;
@@ -752,8 +752,12 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg(
return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
err_lli_free:
- for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
- dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
+ v_lli = txd->v_lli;
+ while (v_lli) {
+ next = v_lli->v_lli_next;
+ dma_pool_free(sdev->pool, v_lli, virt_to_phys(v_lli));
+ v_lli = next;
+ }
kfree(txd);
return NULL;
}
@@ -769,7 +773,7 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic(
struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
struct dma_slave_config *sconfig = &vchan->cfg;
- struct sun6i_dma_lli *v_lli, *prev = NULL;
+ struct sun6i_dma_lli *v_lli, *next, *prev = NULL;
struct sun6i_desc *txd;
dma_addr_t p_lli;
u32 lli_cfg;
@@ -820,8 +824,12 @@ static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_cyclic(
return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
err_lli_free:
- for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
- dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
+ v_lli = txd->v_lli;
+ while (v_lli) {
+ next = v_lli->v_lli_next;
+ dma_pool_free(sdev->pool, v_lli, virt_to_phys(v_lli));
+ v_lli = next;
+ }
kfree(txd);
return NULL;
}
--
2.7.4
