From f0483044c1c96089256cda4cf182eea1ead77fe4 Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Wed, 25 Feb 2015 13:17:48 +0100 Subject: s390/pci: fix possible information leak in mmio syscall Make sure that even in error situations we do not use copy_to_user on uninitialized kernel memory. Cc: stable@vger.kernel.org # 3.19+ Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky --- arch/s390/pci/pci_mmio.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'arch/s390/pci/pci_mmio.c') diff --git a/arch/s390/pci/pci_mmio.c b/arch/s390/pci/pci_mmio.c index 8aa271b3d1ad..b1bb2b72302c 100644 --- a/arch/s390/pci/pci_mmio.c +++ b/arch/s390/pci/pci_mmio.c @@ -64,8 +64,7 @@ SYSCALL_DEFINE3(s390_pci_mmio_write, unsigned long, mmio_addr, if (copy_from_user(buf, user_buffer, length)) goto out; - memcpy_toio(io_addr, buf, length); - ret = 0; + ret = zpci_memcpy_toio(io_addr, buf, length); out: if (buf != local_buf) kfree(buf); @@ -98,16 +97,16 @@ SYSCALL_DEFINE3(s390_pci_mmio_read, unsigned long, mmio_addr, goto out; io_addr = (void __iomem *)((pfn << PAGE_SHIFT) | (mmio_addr & ~PAGE_MASK)); - ret = -EFAULT; - if ((unsigned long) io_addr < ZPCI_IOMAP_ADDR_BASE) + if ((unsigned long) io_addr < ZPCI_IOMAP_ADDR_BASE) { + ret = -EFAULT; goto out; - - memcpy_fromio(buf, io_addr, length); - - if (copy_to_user(user_buffer, buf, length)) + } + ret = zpci_memcpy_fromio(buf, io_addr, length); + if (ret) goto out; + if (copy_to_user(user_buffer, buf, length)) + ret = -EFAULT; - ret = 0; out: if (buf != local_buf) kfree(buf); -- cgit v1.2.3