pci: Add checks to prevent config space overflow
PCIe config space has address range 0-4095. So do not allow reading from addresses outside of this range. Lot of U-Boot drivers do not expect that passed value is not in this range. PCI DM read function is extended to fill read value to all ones or zeros when it fails as U-Boot callers ignores return value. Calling U-Boot command 'pci display.b 0.0.0 0 0x2000' now stops printing config space at the end (before 0x1000 address). Signed-off-by: Pali Rohár <pali@kernel.org> Reviewed-by: Stefan Roese <sr@denx.de>
This commit is contained in:
16
cmd/pci.c
16
cmd/pci.c
@@ -358,6 +358,9 @@ static int pci_cfg_display(struct udevice *dev, ulong addr,
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if (length == 0)
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length = 0x40 / byte_size; /* Standard PCI config space */
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if (addr >= 4096)
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return 1;
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/* Print the lines.
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* once, and all accesses are with the specified bus width.
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*/
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@@ -378,7 +381,10 @@ static int pci_cfg_display(struct udevice *dev, ulong addr,
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rc = 1;
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break;
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}
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} while (nbytes > 0);
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} while (nbytes > 0 && addr < 4096);
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if (rc == 0 && nbytes > 0)
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return 1;
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return (rc);
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}
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@@ -390,6 +396,9 @@ static int pci_cfg_modify(struct udevice *dev, ulong addr, ulong size,
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int nbytes;
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ulong val;
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if (addr >= 4096)
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return 1;
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/* Print the address, followed by value. Then accept input for
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* the next value. A non-converted value exits.
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*/
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@@ -427,7 +436,10 @@ static int pci_cfg_modify(struct udevice *dev, ulong addr, ulong size,
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addr += size;
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}
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}
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} while (nbytes);
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} while (nbytes && addr < 4096);
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if (nbytes)
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return 1;
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return 0;
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}
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