Hi Balou, On 4/14/21 00:24, Lu Baolu wrote: > Hi Gustavo, > > On 4/14/21 3:54 AM, Gustavo A. R. Silva wrote: >> Replace call to memcpy() with just a couple of simple assignments in >> order to fix the following out-of-bounds warning: >> >> drivers/iommu/intel/svm.c:1198:4: warning: 'memcpy' offset [25, 32] from the >> object at 'desc' is out of the bounds of referenced subobject 'qw2' with type >> 'long long unsigned int' at offset 16 [-Warray-bounds] >> >> The problem is that the original code is trying to copy data into a >> couple of struct members adjacent to each other in a single call to >> memcpy(). This causes a legitimate compiler warning because memcpy() >> overruns the length of &desc.qw2. >> >> This helps with the ongoing efforts to globally enable -Warray-bounds >> and get us closer to being able to tighten the FORTIFY_SOURCE routines >> on memcpy(). >> >> Link: https://github.com/KSPP/linux/issues/109 >> Signed-off-by: Gustavo A. R. Silva <gustavo...@kernel.org> >> --- >> drivers/iommu/intel/svm.c | 7 ++++--- >> 1 file changed, 4 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c >> index 5165cea90421..65909f504c50 100644 >> --- a/drivers/iommu/intel/svm.c >> +++ b/drivers/iommu/intel/svm.c >> @@ -1194,9 +1194,10 @@ int intel_svm_page_response(struct device *dev, >> desc.qw1 = QI_PGRP_IDX(prm->grpid) | QI_PGRP_LPIG(last_page); >> desc.qw2 = 0; >> desc.qw3 = 0; >> - if (private_present) >> - memcpy(&desc.qw2, prm->private_data, >> - sizeof(prm->private_data)); > > The same memcpy() is used in multiple places in this file. Did they > compile the same warnings? Or there are multiple patches to fix them > one by one?
I just see one more instance of this same case: 1023 if (req->priv_data_present) 1024 memcpy(&resp.qw2, req->priv_data, 1025 sizeof(req->priv_data)); I missed it and I'll address it in v2. Do you see another one? Thanks for the feedback! -- Gustavo
