[PATCH 1/2] habanalabs: remove access to kernel memory using debugfs

From: Oded Gabbay
Date: Wed Dec 30 2020 - 11:24:56 EST


From: Ofir Bitton <obitton@xxxxxxxxx>

Accessing kernel allocated memory through debugfs should not
be allowed as it introduces a security vulnerability.
We remove the option to read/write kernel memory for all asics.

Signed-off-by: Ofir Bitton <obitton@xxxxxxxxx>
Reviewed-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
Signed-off-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
---
drivers/misc/habanalabs/gaudi/gaudi.c | 8 --------
drivers/misc/habanalabs/goya/goya.c | 12 ------------
2 files changed, 20 deletions(-)

diff --git a/drivers/misc/habanalabs/gaudi/gaudi.c b/drivers/misc/habanalabs/gaudi/gaudi.c
index af49a855d7d6..ac5ad01186c1 100644
--- a/drivers/misc/habanalabs/gaudi/gaudi.c
+++ b/drivers/misc/habanalabs/gaudi/gaudi.c
@@ -5733,8 +5733,6 @@ static int gaudi_debugfs_read32(struct hl_device *hdev, u64 addr, u32 *val)
}
if (hbm_bar_addr == U64_MAX)
rc = -EIO;
- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *val = *(u32 *) phys_to_virt(addr - HOST_PHYS_BASE);
} else {
rc = -EFAULT;
}
@@ -5780,8 +5778,6 @@ static int gaudi_debugfs_write32(struct hl_device *hdev, u64 addr, u32 val)
}
if (hbm_bar_addr == U64_MAX)
rc = -EIO;
- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *(u32 *) phys_to_virt(addr - HOST_PHYS_BASE) = val;
} else {
rc = -EFAULT;
}
@@ -5831,8 +5827,6 @@ static int gaudi_debugfs_read64(struct hl_device *hdev, u64 addr, u64 *val)
}
if (hbm_bar_addr == U64_MAX)
rc = -EIO;
- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *val = *(u64 *) phys_to_virt(addr - HOST_PHYS_BASE);
} else {
rc = -EFAULT;
}
@@ -5881,8 +5875,6 @@ static int gaudi_debugfs_write64(struct hl_device *hdev, u64 addr, u64 val)
}
if (hbm_bar_addr == U64_MAX)
rc = -EIO;
- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *(u64 *) phys_to_virt(addr - HOST_PHYS_BASE) = val;
} else {
rc = -EFAULT;
}
diff --git a/drivers/misc/habanalabs/goya/goya.c b/drivers/misc/habanalabs/goya/goya.c
index da12462bd888..71d5a2620421 100644
--- a/drivers/misc/habanalabs/goya/goya.c
+++ b/drivers/misc/habanalabs/goya/goya.c
@@ -4121,9 +4121,6 @@ static int goya_debugfs_read32(struct hl_device *hdev, u64 addr, u32 *val)
if (ddr_bar_addr == U64_MAX)
rc = -EIO;

- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *val = *(u32 *) phys_to_virt(addr - HOST_PHYS_BASE);
-
} else {
rc = -EFAULT;
}
@@ -4177,9 +4174,6 @@ static int goya_debugfs_write32(struct hl_device *hdev, u64 addr, u32 val)
if (ddr_bar_addr == U64_MAX)
rc = -EIO;

- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *(u32 *) phys_to_virt(addr - HOST_PHYS_BASE) = val;
-
} else {
rc = -EFAULT;
}
@@ -4222,9 +4216,6 @@ static int goya_debugfs_read64(struct hl_device *hdev, u64 addr, u64 *val)
if (ddr_bar_addr == U64_MAX)
rc = -EIO;

- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *val = *(u64 *) phys_to_virt(addr - HOST_PHYS_BASE);
-
} else {
rc = -EFAULT;
}
@@ -4265,9 +4256,6 @@ static int goya_debugfs_write64(struct hl_device *hdev, u64 addr, u64 val)
if (ddr_bar_addr == U64_MAX)
rc = -EIO;

- } else if (addr >= HOST_PHYS_BASE && !iommu_present(&pci_bus_type)) {
- *(u64 *) phys_to_virt(addr - HOST_PHYS_BASE) = val;
-
} else {
rc = -EFAULT;
}
--
2.25.1