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| author | Dan Williams <dan.j.williams@intel.com> | 2016-11-16 09:00:38 -0800 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2016-11-16 09:00:38 -0800 |
| commit | 4cb19355ea19995941ccaad115dbfac6b75215ca (patch) | |
| tree | ec4bbe77017ce2002940f2e9c9b502a7abf648d4 | |
| parent | 6a84fb4b4e439a8ef0ce19ec7e7661ad76f655c9 (diff) | |
| download | linux-4cb19355ea19995941ccaad115dbfac6b75215ca.tar.gz linux-4cb19355ea19995941ccaad115dbfac6b75215ca.tar.bz2 linux-4cb19355ea19995941ccaad115dbfac6b75215ca.zip | |
device-dax: fail all private mapping attempts
The device-dax implementation originally tried to be tricky and allow
private read-only mappings, but in the process allowed writable
MAP_PRIVATE + MAP_NORESERVE mappings. For simplicity and predictability
just fail all private mapping attempts since device-dax memory is
statically allocated and will never support overcommit.
Cc: <stable@vger.kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap")
Reported-by: Pawel Lebioda <pawel.lebioda@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| -rw-r--r-- | drivers/dax/dax.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c index 0e499bfca41c..3d94ff20fdca 100644 --- a/drivers/dax/dax.c +++ b/drivers/dax/dax.c @@ -270,8 +270,8 @@ static int check_vma(struct dax_dev *dax_dev, struct vm_area_struct *vma, if (!dax_dev->alive) return -ENXIO; - /* prevent private / writable mappings from being established */ - if ((vma->vm_flags & (VM_NORESERVE|VM_SHARED|VM_WRITE)) == VM_WRITE) { + /* prevent private mappings from being established */ + if ((vma->vm_flags & VM_SHARED) != VM_SHARED) { dev_info(dev, "%s: %s: fail, attempted private mapping\n", current->comm, func); return -EINVAL; |