From 38c0a74fe06da3be133cae3fb7bde6a9438e698b 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() 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 Cc: stable@vger.kernel.org # v3.12+ Patchwork: https://patchwork.linux-mips.org/patch/19829/ --- arch/mips/pci/pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c index 9632436d74d7..c2e94cf5ecda 100644 --- a/arch/mips/pci/pci.c +++ b/arch/mips/pci/pci.c @@ -54,5 +54,5 @@ 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; }