On Thu, Jan 17, 2019 at 12:42:04PM -0800, Dennis Dalessandro wrote:
> From: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>
>
> Applications that use the stack for execution purposes cause
> PSM jobs to fail during mmap().
>
> Both Fortran (non-standard format parsing) and C (callback
> functions located in the stack) applications can be written
> such that stack execution is required.
>
> Because of this the EXECSTACK bit can be automatically set at link
> time for any application.
>
> On application load, the ELF loader evaluates the EXECSTACK bit
> for the application and it's linked libraries. It will set the
> process VM flags to allow the stack to include the VM_EXEC bit
> if the EXECSTACK bit is set. This flag is propagated to the
> driver during the mmap() call in the vma flag bits.
>
> Checking for this bit and failing the request with EPERM is overly
> conservative and will break any PSM application that has the bit set.
>
> Remove the VM_EXEC flag from the check.
>
> Cc: <stable@xxxxxxxxxxxxxxx> #v4.14+
> Fixes: 12220267645c ("IB/hfi: Protect against writable mmap")
> Reviewed-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx>
> Reviewed-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
> Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> Signed-off-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>
> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
> ---
> drivers/infiniband/hw/hfi1/file_ops.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
applied to for-next
Thanks,
Jason
