In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: TSO: Fix unbalanced DMA map/unmap for non-paged SKB data
In case the non-paged data of a SKB carries protocol header and protocol
payload to be transmitted on a certain platform that the DMA AXI address
width is configured to 40-bit/48-bit, or the size of the non-paged data
is bigger than TSO_MAX_BUFF_SIZE on a certain platform that the DMA AXI
address width is configured to 32-bit, then this SKB requires at least
two DMA transmit descriptors to serve it.
For example, three descriptors are allocated to split one DMA buffer
mapped from one piece of non-paged data:
dma_desc[N + 0],
dma_desc[N + 1],
dma_desc[N + 2].
Then three elements of tx_q->tx_skbuff_dma[] will be allocated to hold
extra information to be reused in stmmac_tx_clean():
tx_q->tx_skbuff_dma[N + 0],
tx_q->tx_skbuff_dma[N + 1],
tx_q->tx_skbuff_dma[N + 2].
Now we focus on tx_q->tx_skbuff_dma[entry].buf, which is the DMA buffer
address returned by DMA mapping call. stmmac_tx_clean() will try to
unmap the DMA buffer _ONLY_IF_ tx_q->tx_skbuff_dma[entry].buf
is a valid buffer address.
The expected behavior that saves DMA buffer address of this non-paged
data to tx_q->tx_skbuff_dma[entry].buf is:
tx_q->tx_skbuff_dma[N + 0].buf = NULL;
tx_q->tx_skbuff_dma[N + 1].buf = NULL;
tx_q->tx_skbuff_dma[N + 2].buf = dma_map_single();
Unfortunately, the current code misbehaves like this:
tx_q->tx_skbuff_dma[N + 0].buf = dma_map_single();
tx_q->tx_skbuff_dma[N + 1].buf = NULL;
tx_q->tx_skbuff_dma[N + 2].buf = NULL;
On the stmmac_tx_clean() side, when dma_desc[N + 0] is closed by the
DMA engine, tx_q->tx_skbuff_dma[N + 0].buf is a valid buffer address
obviously, then the DMA buffer will be unmapped immediately.
There may be a rare case that the DMA engine does not finish the
pending dma_desc[N + 1], dma_desc[N + 2] yet. Now things will go
horribly wrong, DMA is going to access a unmapped/unreferenced memory
region, corrupted data will be transmited or iommu fault will be
triggered :(
In contrast, the for-loop that maps SKB fragments behaves perfectly
as expected, and that is how the driver should do for both non-paged
data and paged frags actually.
This patch corrects DMA map/unmap sequences by fixing the array index
for tx_q->tx_skbuff_dma[entry].buf when assigning DMA buffer address.
Tested and verified on DWXGMAC CORE 3.20a
Metrics
Affected Vendors & Products
References
History
Fri, 22 Nov 2024 18:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
First Time appeared |
Linux
Linux linux Kernel |
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Weaknesses | NVD-CWE-noinfo | |
CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.12:rc5:*:*:*:*:*:* |
|
Vendors & Products |
Linux
Linux linux Kernel |
Fri, 22 Nov 2024 14:00:00 +0000
Type | Values Removed | Values Added |
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References |
| |
Metrics |
threat_severity
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cvssV3_1
|
Tue, 19 Nov 2024 17:30:00 +0000
Type | Values Removed | Values Added |
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Description | In the Linux kernel, the following vulnerability has been resolved: net: stmmac: TSO: Fix unbalanced DMA map/unmap for non-paged SKB data In case the non-paged data of a SKB carries protocol header and protocol payload to be transmitted on a certain platform that the DMA AXI address width is configured to 40-bit/48-bit, or the size of the non-paged data is bigger than TSO_MAX_BUFF_SIZE on a certain platform that the DMA AXI address width is configured to 32-bit, then this SKB requires at least two DMA transmit descriptors to serve it. For example, three descriptors are allocated to split one DMA buffer mapped from one piece of non-paged data: dma_desc[N + 0], dma_desc[N + 1], dma_desc[N + 2]. Then three elements of tx_q->tx_skbuff_dma[] will be allocated to hold extra information to be reused in stmmac_tx_clean(): tx_q->tx_skbuff_dma[N + 0], tx_q->tx_skbuff_dma[N + 1], tx_q->tx_skbuff_dma[N + 2]. Now we focus on tx_q->tx_skbuff_dma[entry].buf, which is the DMA buffer address returned by DMA mapping call. stmmac_tx_clean() will try to unmap the DMA buffer _ONLY_IF_ tx_q->tx_skbuff_dma[entry].buf is a valid buffer address. The expected behavior that saves DMA buffer address of this non-paged data to tx_q->tx_skbuff_dma[entry].buf is: tx_q->tx_skbuff_dma[N + 0].buf = NULL; tx_q->tx_skbuff_dma[N + 1].buf = NULL; tx_q->tx_skbuff_dma[N + 2].buf = dma_map_single(); Unfortunately, the current code misbehaves like this: tx_q->tx_skbuff_dma[N + 0].buf = dma_map_single(); tx_q->tx_skbuff_dma[N + 1].buf = NULL; tx_q->tx_skbuff_dma[N + 2].buf = NULL; On the stmmac_tx_clean() side, when dma_desc[N + 0] is closed by the DMA engine, tx_q->tx_skbuff_dma[N + 0].buf is a valid buffer address obviously, then the DMA buffer will be unmapped immediately. There may be a rare case that the DMA engine does not finish the pending dma_desc[N + 1], dma_desc[N + 2] yet. Now things will go horribly wrong, DMA is going to access a unmapped/unreferenced memory region, corrupted data will be transmited or iommu fault will be triggered :( In contrast, the for-loop that maps SKB fragments behaves perfectly as expected, and that is how the driver should do for both non-paged data and paged frags actually. This patch corrects DMA map/unmap sequences by fixing the array index for tx_q->tx_skbuff_dma[entry].buf when assigning DMA buffer address. Tested and verified on DWXGMAC CORE 3.20a | |
Title | net: stmmac: TSO: Fix unbalanced DMA map/unmap for non-paged SKB data | |
References |
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MITRE
Status: PUBLISHED
Assigner: Linux
Published: 2024-11-19T17:19:40.912Z
Updated: 2024-12-19T09:38:10.578Z
Reserved: 2024-11-19T17:17:24.974Z
Link: CVE-2024-53058
Vulnrichment
No data.
NVD
Status : Analyzed
Published: 2024-11-19T18:15:25.767
Modified: 2024-11-22T17:53:32.500
Link: CVE-2024-53058
Redhat