diff options
| author | Juergen Gross <jgross@suse.com> | 2021-04-23 07:40:38 +0200 |
|---|---|---|
| committer | Juergen Gross <jgross@suse.com> | 2021-05-10 09:32:00 +0200 |
| commit | 970655aa9b42461f8394e4457307005bdeee14d9 (patch) | |
| tree | 3181bb4b00415833f5f2d3c39548bbd3189910d2 | |
| parent | 6efb943b8616ec53a5e444193dccf1af9ad627b5 (diff) | |
xen/gntdev: fix gntdev_mmap() error exit path
Commit d3eeb1d77c5d0af ("xen/gntdev: use mmu_interval_notifier_insert")
introduced an error in gntdev_mmap(): in case the call of
mmu_interval_notifier_insert_locked() fails the exit path should not
call mmu_interval_notifier_remove(), as this might result in NULL
dereferences.
One reason for failure is e.g. a signal pending for the running
process.
Fixes: d3eeb1d77c5d0af ("xen/gntdev: use mmu_interval_notifier_insert")
Cc: stable@vger.kernel.org
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Link: https://lore.kernel.org/r/20210423054038.26696-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
| -rw-r--r-- | drivers/xen/gntdev.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index f01d58c7a042..a3e7be96527d 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -1017,8 +1017,10 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) err = mmu_interval_notifier_insert_locked( &map->notifier, vma->vm_mm, vma->vm_start, vma->vm_end - vma->vm_start, &gntdev_mmu_ops); - if (err) + if (err) { + map->vma = NULL; goto out_unlock_put; + } } mutex_unlock(&priv->lock); |