3.16.81-rc1 review patch. If anyone has any objections, please let me know.
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From: Ben Hutchings ben@decadent.org.uk
commit cad46039e4c99812db067c8ac22a864960e7acc4 upstream.
ql_alloc_large_buffers() has the usual RX buffer allocation loop where it allocates skbs and maps them for DMA. It also treats failure as a fatal error.
There are (at least) three bugs in the error paths:
1. ql_free_large_buffers() assumes that the lrg_buf[] entry for the first buffer that couldn't be allocated will have .skb == NULL. But the qla_buf[] array is not zero-initialised.
2. ql_free_large_buffers() DMA-unmaps all skbs in lrg_buf[]. This is incorrect for the last allocated skb, if DMA mapping failed.
3. Commit 1acb8f2a7a9f ("net: qlogic: Fix memory leak in ql_alloc_large_buffers") added a direct call to dev_kfree_skb_any() after the skb is recorded in lrg_buf[], so ql_free_large_buffers() will double-free it.
The bugs are somewhat inter-twined, so fix them all at once:
* Clear each entry in qla_buf[] before attempting to allocate an skb for it. This goes half-way to fixing bug 1. * Set the .skb field only after the skb is DMA-mapped. This fixes the rest.
Fixes: 1357bfcf7106 ("qla3xxx: Dynamically size the rx buffer queue ...") Fixes: 0f8ab89e825f ("qla3xxx: Check return code from pci_map_single() ...") Fixes: 1acb8f2a7a9f ("net: qlogic: Fix memory leak in ql_alloc_large_buffers") Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: David S. Miller davem@davemloft.net --- drivers/net/ethernet/qlogic/qla3xxx.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/net/ethernet/qlogic/qla3xxx.c +++ b/drivers/net/ethernet/qlogic/qla3xxx.c @@ -2758,6 +2758,9 @@ static int ql_alloc_large_buffers(struct int err;
for (i = 0; i < qdev->num_large_buffers; i++) { + lrg_buf_cb = &qdev->lrg_buf[i]; + memset(lrg_buf_cb, 0, sizeof(struct ql_rcv_buf_cb)); + skb = netdev_alloc_skb(qdev->ndev, qdev->lrg_buffer_len); if (unlikely(!skb)) { @@ -2768,11 +2771,7 @@ static int ql_alloc_large_buffers(struct ql_free_large_buffers(qdev); return -ENOMEM; } else { - - lrg_buf_cb = &qdev->lrg_buf[i]; - memset(lrg_buf_cb, 0, sizeof(struct ql_rcv_buf_cb)); lrg_buf_cb->index = i; - lrg_buf_cb->skb = skb; /* * We save some space to copy the ethhdr from first * buffer @@ -2794,6 +2793,7 @@ static int ql_alloc_large_buffers(struct return -ENOMEM; }
+ lrg_buf_cb->skb = skb; dma_unmap_addr_set(lrg_buf_cb, mapaddr, map); dma_unmap_len_set(lrg_buf_cb, maplen, qdev->lrg_buffer_len -