commit 38c0a74fe06da3be133cae3fb7bde6a9438e698b upstream.
The MIPS implementation of pci_resource_to_user() introduced in v3.12 by
commit 4c2924b725fb ("MIPS: PCI: Use pci_resource_to_user to map pci
memory space properly") incorrectly sets *end to the address of the
byte after the resource, rather than the last byte of the resource.
This results in userland seeing resources as a byte larger than they
actually are, for example a 32 byte BAR will be reported by a tool such
as lspci as being 33 bytes in size:
Region 2: I/O ports at 1000 [disabled] [size=33]
Correct this by subtracting one from the calculated end address,
reporting the correct address to userland.
Signed-off-by: Paul Burton <paul.burton@xxxxxxxx>
Reported-by: Rui Wang <rui.wang@xxxxxxxxxxxxx>
Fixes: 4c2924b725fb ("MIPS: PCI: Use pci_resource_to_user to map pci memory space properly")
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Wolfgang Grandegger <wg@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx # v3.12+
Patchwork: https://patchwork.linux-mips.org/patch/19829/
---
arch/mips/include/asm/pci.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h
index 98c31e5d9579..a7bc901819c8 100644
--- a/arch/mips/include/asm/pci.h
+++ b/arch/mips/include/asm/pci.h
@@ -89,7 +89,7 @@ static inline void pci_resource_to_user(const struct pci_dev *dev, int bar,
phys_addr_t size = resource_size(rsrc);
*start = fixup_bigphys_addr(rsrc->start, size);
- *end = rsrc->start + size;
+ *end = rsrc->start + size - 1;
}
/*
--
2.18.0
