diff options
| author | Sebastian Ott <sebott@linux.vnet.ibm.com> | 2015-02-25 13:17:48 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-02-26 09:24:48 +0100 |
| commit | f0483044c1c96089256cda4cf182eea1ead77fe4 (patch) | |
| tree | 796dbcd919384e53c5bab81ccd14e6aed6b4a663 /arch/s390/pci/pci_mmio.c | |
| parent | 3a9f9183bdd341a25c7805d96bbd78a31d559381 (diff) | |
| download | lwn-f0483044c1c96089256cda4cf182eea1ead77fe4.tar.gz lwn-f0483044c1c96089256cda4cf182eea1ead77fe4.zip | |
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 <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/pci/pci_mmio.c')
| -rw-r--r-- | arch/s390/pci/pci_mmio.c | 17 |
1 files changed, 8 insertions, 9 deletions
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); |