From 028118a5f09a9c807e6b43e2231efdff9f224c74 Mon Sep 17 00:00:00 2001
From: Michael Buesch <mb@bu3sch.de>
Date: Thu, 12 Jun 2008 11:58:56 +0200
Subject: [PATCH] b43: Fix possible NULL pointer dereference in DMA code
This fixes a possible NULL pointer dereference in an error path of the
DMA allocation error checking code. This is also necessary for a future
DMA API change that is on its way into the mainline kernel that adds
an additional dev parameter to dma_mapping_error().
This patch moves the whole struct b43_dmaring struct initialization
right before any DMA allocation operation.
Reported-by: Miles Lane <miles.lane@gmail.com>
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
drivers/net/wireless/b43/dma.c | 65 +++++++++++++++++-----------------
1 file changed, 32 insertions(+), 33 deletions(-)
diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c
index 6dcbb3c87e72..e23f2f172bd7 100644
--- a/drivers/net/wireless/b43/dma.c
+++ b/drivers/net/wireless/b43/dma.c
@@ -795,24 +795,49 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
{
struct b43_dmaring *ring;
int err;
- int nr_slots;
dma_addr_t dma_test;
ring = kzalloc(sizeof(*ring), GFP_KERNEL);
if (!ring)
goto out;
- ring->type = type;
- nr_slots = B43_RXRING_SLOTS;
+ ring->nr_slots = B43_RXRING_SLOTS;
if (for_tx)
- nr_slots = B43_TXRING_SLOTS;
+ ring->nr_slots = B43_TXRING_SLOTS;
- ring->meta = kcalloc(nr_slots, sizeof(struct b43_dmadesc_meta),
+ ring->meta = kcalloc(ring->nr_slots, sizeof(struct b43_dmadesc_meta),
GFP_KERNEL);
if (!ring->meta)
goto err_kfree_ring;
+
+ ring->type = type;
+ ring->dev = dev;
+ ring->mmio_base = b43_dmacontroller_base(type, controller_index);
+ ring->index = controller_index;
+ if (type == B43_DMA_64BIT)
+ ring->ops = &dma64_ops;
+ else
+ ring->ops = &dma32_ops;
if (for_tx) {
- ring->txhdr_cache = kcalloc(nr_slots,
+ ring->tx = 1;
+ ring->current_slot = -1;
+ } else {
+ if (ring->index == 0) {
+ ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
+ ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
+ } else if (ring->index == 3) {
+ ring->rx_buffersize = B43_DMA3_RX_BUFFERSIZE;
+ ring->frameoffset = B43_DMA3_RX_FRAMEOFFSET;
+ } else
+ B43_WARN_ON(1);
+ }
+ spin_lock_init(&ring->lock);
+#ifdef CONFIG_B43_DEBUG
+ ring->last_injected_overflow = jiffies;
+#endif
+
+ if (for_tx) {
+ ring->txhdr_cache = kcalloc(ring->nr_slots,
b43_txhdr_size(dev),
GFP_KERNEL);
if (!ring->txhdr_cache)
@@ -828,7 +853,7 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
b43_txhdr_size(dev), 1)) {
/* ugh realloc */
kfree(ring->txhdr_cache);
- ring->txhdr_cache = kcalloc(nr_slots,
+ ring->txhdr_cache = kcalloc(ring->nr_slots,
b43_txhdr_size(dev),
GFP_KERNEL | GFP_DMA);
if (!ring->txhdr_cache)
@@ -853,32 +878,6 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
DMA_TO_DEVICE);
}
- ring->dev = dev;
- ring->nr_slots = nr_slots;
- ring->mmio_base = b43_dmacontroller_base(type, controller_index);
- ring->index = controller_index;
- if (type == B43_DMA_64BIT)
- ring->ops = &dma64_ops;
- else
- ring->ops = &dma32_ops;
- if (for_tx) {
- ring->tx = 1;
- ring->current_slot = -1;
- } else {
- if (ring->index == 0) {
- ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
- ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
- } else if (ring->index == 3) {
- ring->rx_buffersize = B43_DMA3_RX_BUFFERSIZE;
- ring->frameoffset = B43_DMA3_RX_FRAMEOFFSET;
- } else
- B43_WARN_ON(1);
- }
- spin_lock_init(&ring->lock);
-#ifdef CONFIG_B43_DEBUG
- ring->last_injected_overflow = jiffies;
-#endif
-
err = alloc_ringmemory(ring);
if (err)
goto err_kfree_txhdr_cache;
--
2.20.1