| Message ID | 1607546066-2240-6-git-send-email-mjrosato@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | s390x/pci: Fixing s390 vfio-pci ISM support | expand |
On Wed, 9 Dec 2020 15:34:23 -0500 Matthew Rosato <mjrosato@linux.ibm.com> wrote: > In pcistb_service_handler, a call is made to validate that the memory > region can be accessed. However, the call is made using the entire length > of the pcistb operation, which can be larger than the allowed memory > access size (8). Since we already know that the provided buffer is a > multiple of 8, fix the call to memory_region_access_valid to iterate > over the memory region in the same way as the subsequent call to > memory_region_dispatch_write. > > Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> > --- > hw/s390x/s390-pci-inst.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c > index b07ef2a..a5270d0 100644 > --- a/hw/s390x/s390-pci-inst.c > +++ b/hw/s390x/s390-pci-inst.c > @@ -795,9 +795,11 @@ static int pcistb_default(S390PCIBusDevice *pbdev, S390CPU *cpu, > mr = s390_get_subregion(mr, offset, len); > offset -= mr->addr; > > - if (!memory_region_access_valid(mr, offset, len, true, > - MEMTXATTRS_UNSPECIFIED)) { > - return -EINVAL; > + for (i = 0; i < len / 8; i++) { > + if (!memory_region_access_valid(mr, offset + i * 8, 8, true, > + MEMTXATTRS_UNSPECIFIED)) { > + return -EINVAL; > + } > } > > if (s390_cpu_virt_mem_read(cpu, gaddr, ar, pbdev->pcistb_buf, len)) { Hm, that looks like a fix that's applicable for the current code base as well... do you want to split this out?
diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c index b07ef2a..a5270d0 100644 --- a/hw/s390x/s390-pci-inst.c +++ b/hw/s390x/s390-pci-inst.c @@ -795,9 +795,11 @@ static int pcistb_default(S390PCIBusDevice *pbdev, S390CPU *cpu, mr = s390_get_subregion(mr, offset, len); offset -= mr->addr; - if (!memory_region_access_valid(mr, offset, len, true, - MEMTXATTRS_UNSPECIFIED)) { - return -EINVAL; + for (i = 0; i < len / 8; i++) { + if (!memory_region_access_valid(mr, offset + i * 8, 8, true, + MEMTXATTRS_UNSPECIFIED)) { + return -EINVAL; + } } if (s390_cpu_virt_mem_read(cpu, gaddr, ar, pbdev->pcistb_buf, len)) {
In pcistb_service_handler, a call is made to validate that the memory region can be accessed. However, the call is made using the entire length of the pcistb operation, which can be larger than the allowed memory access size (8). Since we already know that the provided buffer is a multiple of 8, fix the call to memory_region_access_valid to iterate over the memory region in the same way as the subsequent call to memory_region_dispatch_write. Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> --- hw/s390x/s390-pci-inst.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)