Commit 38f49a51 authored by Eric W. Biederman's avatar Eric W. Biederman Committed by Greg Kroah-Hartman

sysfs: only access bin file vm_ops with the active lock

bb->vm_ops is a cached copy of the vm_ops of the underlying
sysfs bin file, which means that after sysfs_bin_remove_file
completes it is only longer valid to deference bb->vm_ops.

So move all of the tests of bb->vm_ops inside of where
we hold the sysfs active lock.
Signed-off-by: default avatarEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent a6849fa1
......@@ -179,13 +179,14 @@ static void bin_vma_open(struct vm_area_struct *vma)
struct bin_buffer *bb = file->private_data;
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
if (!bb->vm_ops || !bb->vm_ops->open)
if (!bb->vm_ops)
return;
if (!sysfs_get_active(attr_sd))
return;
bb->vm_ops->open(vma);
if (bb->vm_ops->open)
bb->vm_ops->open(vma);
sysfs_put_active(attr_sd);
}
......@@ -197,13 +198,15 @@ static int bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
int ret;
if (!bb->vm_ops || !bb->vm_ops->fault)
if (!bb->vm_ops)
return VM_FAULT_SIGBUS;
if (!sysfs_get_active(attr_sd))
return VM_FAULT_SIGBUS;
ret = bb->vm_ops->fault(vma, vmf);
ret = VM_FAULT_SIGBUS;
if (bb->vm_ops->fault)
ret = bb->vm_ops->fault(vma, vmf);
sysfs_put_active(attr_sd);
return ret;
......@@ -219,13 +222,12 @@ static int bin_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
if (!bb->vm_ops)
return VM_FAULT_SIGBUS;
if (!bb->vm_ops->page_mkwrite)
return 0;
if (!sysfs_get_active(attr_sd))
return VM_FAULT_SIGBUS;
ret = bb->vm_ops->page_mkwrite(vma, vmf);
ret = 0;
if (bb->vm_ops->page_mkwrite)
ret = bb->vm_ops->page_mkwrite(vma, vmf);
sysfs_put_active(attr_sd);
return ret;
......@@ -239,13 +241,15 @@ static int bin_access(struct vm_area_struct *vma, unsigned long addr,
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
int ret;
if (!bb->vm_ops || !bb->vm_ops->access)
if (!bb->vm_ops)
return -EINVAL;
if (!sysfs_get_active(attr_sd))
return -EINVAL;
ret = bb->vm_ops->access(vma, addr, buf, len, write);
ret = -EINVAL;
if (bb->vm_ops->access)
ret = bb->vm_ops->access(vma, addr, buf, len, write);
sysfs_put_active(attr_sd);
return ret;
......@@ -259,13 +263,15 @@ static int bin_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
int ret;
if (!bb->vm_ops || !bb->vm_ops->set_policy)
if (!bb->vm_ops)
return 0;
if (!sysfs_get_active(attr_sd))
return -EINVAL;
ret = bb->vm_ops->set_policy(vma, new);
ret = 0;
if (bb->vm_ops->set_policy)
ret = bb->vm_ops->set_policy(vma, new);
sysfs_put_active(attr_sd);
return ret;
......@@ -279,13 +285,15 @@ static struct mempolicy *bin_get_policy(struct vm_area_struct *vma,
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
struct mempolicy *pol;
if (!bb->vm_ops || !bb->vm_ops->get_policy)
if (!bb->vm_ops)
return vma->vm_policy;
if (!sysfs_get_active(attr_sd))
return vma->vm_policy;
pol = bb->vm_ops->get_policy(vma, addr);
pol = vma->vm_policy;
if (bb->vm_ops->get_policy)
pol = bb->vm_ops->get_policy(vma, addr);
sysfs_put_active(attr_sd);
return pol;
......@@ -299,13 +307,15 @@ static int bin_migrate(struct vm_area_struct *vma, const nodemask_t *from,
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
int ret;
if (!bb->vm_ops || !bb->vm_ops->migrate)
if (!bb->vm_ops)
return 0;
if (!sysfs_get_active(attr_sd))
return 0;
ret = bb->vm_ops->migrate(vma, from, to, flags);
ret = 0;
if (bb->vm_ops->migrate)
ret = bb->vm_ops->migrate(vma, from, to, flags);
sysfs_put_active(attr_sd);
return ret;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment