[PATCHv5 1/6] x86/vdso: unmap vdso blob on vvar mapping failure

From: Dmitry Safonov
Date: Mon Sep 05 2016 - 09:37:39 EST


If remapping of vDSO blob failed on vvar mapping,
we need to unmap previously mapped vDSO blob.

Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: x86@xxxxxxxxxx
Cc: Cyrill Gorcunov <gorcunov@xxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
Signed-off-by: Dmitry Safonov <dsafonov@xxxxxxxxxxxxx>
Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/entry/vdso/vma.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index f840766659a8..3bab6ba3ffc5 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -238,12 +238,14 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr)

if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
- goto up_fail;
+ do_munmap(mm, text_start, image->size);
}

up_fail:
- if (ret)
+ if (ret) {
current->mm->context.vdso = NULL;
+ current->mm->context.vdso_image = NULL;
+ }

up_write(&mm->mmap_sem);
return ret;
--
2.9.0