From a7233dbfa3e4e2c7a43e53a51fed043d19876d55 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Thu, 12 Jul 2018 09:33:04 -0700 Subject: [PATCH] MIPS: Fix off-by-one in pci_resource_to_user() 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 Reported-by: Rui Wang Fixes: 4c2924b725fb ("MIPS: PCI: Use pci_resource_to_user to map pci memory space properly") Cc: James Hogan Cc: Ralf Baechle Cc: Wolfgang Grandegger Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/19829/ [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings --- 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 974b0e308963..6a72f1036912 100644 --- a/arch/mips/include/asm/pci.h +++ b/arch/mips/include/asm/pci.h @@ -87,7 +87,7 @@ static inline void pci_resource_to_user(const struct pci_dev *dev, int bar, phys_t size = resource_size(rsrc); *start = fixup_bigphys_addr(rsrc->start, size); - *end = rsrc->start + size; + *end = rsrc->start + size - 1; } /*