KVM uses anon_inode_get() to allocate file descriptors as part
of some of its ioctls. But those ioctls are lacking a flag argument
allowing userspace to choose options for the newly opened file descriptor.

In such case it's advised to use O_CLOEXEC by default so that
userspace is allowed to choose, without race, if the file descriptor
is going to be inherited across exec().

This patch set O_CLOEXEC flag on all file descriptors created
with anon_inode_getfd() to not leak file descriptors across exec().

Signed-off-by: Yann Droneaud <ydrone...@opteya.com>
Link: http://lkml.kernel.org/r/cover.1377372576.git.ydrone...@opteya.com

---
 arch/powerpc/kvm/book3s_64_mmu_hv.c | 2 +-
 arch/powerpc/kvm/book3s_64_vio.c    | 2 +-
 arch/powerpc/kvm/book3s_hv.c        | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c 
b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 710d313..f7c9e8a 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -1579,7 +1579,7 @@ int kvm_vm_ioctl_get_htab_fd(struct kvm *kvm, struct 
kvm_get_htab_fd *ghf)
        ctx->first_pass = 1;
 
        rwflag = (ghf->flags & KVM_GET_HTAB_WRITE) ? O_WRONLY : O_RDONLY;
-       ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag);
+       ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag | 
O_CLOEXEC);
        if (ret < 0) {
                kvm_put_kvm(kvm);
                return ret;
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index b2d3f3b..54cf9bc 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -136,7 +136,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
        mutex_unlock(&kvm->lock);
 
        return anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
-                               stt, O_RDWR);
+                               stt, O_RDWR | O_CLOEXEC);
 
 fail:
        if (stt) {
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index e8d51cb..3503829 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1556,7 +1556,7 @@ long kvm_vm_ioctl_allocate_rma(struct kvm *kvm, struct 
kvm_allocate_rma *ret)
        if (!ri)
                return -ENOMEM;
 
-       fd = anon_inode_getfd("kvm-rma", &kvm_rma_fops, ri, O_RDWR);
+       fd = anon_inode_getfd("kvm-rma", &kvm_rma_fops, ri, O_RDWR | O_CLOEXEC);
        if (fd < 0)
                kvm_release_rma(ri);
 
-- 
1.8.3.1

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