The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 38c0a74fe06da3be133cae3fb7bde6a9438e698b Mon Sep 17 00:00:00 2001
From: Paul Burton paul.burton@mips.com 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 paul.burton@mips.com Reported-by: Rui Wang rui.wang@windriver.com Fixes: 4c2924b725fb ("MIPS: PCI: Use pci_resource_to_user to map pci memory space properly") Cc: James Hogan jhogan@kernel.org Cc: Ralf Baechle ralf@linux-mips.org Cc: Wolfgang Grandegger wg@grandegger.com Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # v3.12+ Patchwork: https://patchwork.linux-mips.org/patch/19829/
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; }