diff options
author | Matan Barak <matanb@mellanox.com> | 2016-04-14 16:52:10 +0300 |
---|---|---|
committer | Doug Ledford <dledford@redhat.com> | 2016-05-13 19:40:03 -0400 |
commit | 6cbac1e4cd0e0110b4be38c201fc055249dfd365 (patch) | |
tree | d361a3fe422482b0a0876cab0362ca7084a73d27 | |
parent | ee71b9681df6b71b7fa110d42200bec05dfaf19a (diff) | |
download | op-kernel-dev-6cbac1e4cd0e0110b4be38c201fc055249dfd365.zip op-kernel-dev-6cbac1e4cd0e0110b4be38c201fc055249dfd365.tar.gz |
IB/mlx5: Allow mapping the free running counter on PROT_EXEC
The current mlx5 code disallows mapping the free running counter of
mlx5 based hardwares when PROT_EXEC is set.
Although this behaviour is correct, Linux does add an implicit VM_EXEC
to the vm_flags if the READ_IMPLIES_EXEC bit is set in the process
personality. This happens for example if the process stack is
executable.
This causes libmlx5 to output a warning and prevents the user from
reading the free running clock.
Executing the init segment of the hardware isn't a security risk
(at least no more than executing a process own stack), so we just
prevent writes to there.
Fixes: d69e3bcf7976 ('IB/mlx5: Mmap the HCA's core clock register to
user-space')
Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
-rw-r--r-- | drivers/infiniband/hw/mlx5/main.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index 6ad0489..f2a1ad9 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -1108,7 +1108,7 @@ static int mlx5_ib_mmap(struct ib_ucontext *ibcontext, struct vm_area_struct *vm if (vma->vm_end - vma->vm_start != PAGE_SIZE) return -EINVAL; - if (vma->vm_flags & (VM_WRITE | VM_EXEC)) + if (vma->vm_flags & VM_WRITE) return -EPERM; /* Don't expose to user-space information it shouldn't have */ |