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-rw-r--r--fs/proc/base.c53
-rw-r--r--fs/proc/generic.c4
-rw-r--r--fs/proc/inode.c9
-rw-r--r--fs/proc/proc_sysctl.c31
4 files changed, 68 insertions, 29 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 08cba2c3b612..b20962c71a52 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1795,10 +1795,16 @@ static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat
*/
static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct inode *inode = dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
+ struct inode *inode;
+ struct task_struct *task;
const struct cred *cred;
+ if (nd && nd->flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ inode = dentry->d_inode;
+ task = get_proc_task(inode);
+
if (task) {
if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
task_dumpable(task)) {
@@ -1820,7 +1826,7 @@ static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
return 0;
}
-static int pid_delete_dentry(struct dentry * dentry)
+static int pid_delete_dentry(const struct dentry * dentry)
{
/* Is the task we represent dead?
* If so, then don't put the dentry on the lru list,
@@ -1964,12 +1970,19 @@ static int proc_fd_link(struct inode *inode, struct path *path)
static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct inode *inode = dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
- int fd = proc_fd(inode);
+ struct inode *inode;
+ struct task_struct *task;
+ int fd;
struct files_struct *files;
const struct cred *cred;
+ if (nd && nd->flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ inode = dentry->d_inode;
+ task = get_proc_task(inode);
+ fd = proc_fd(inode);
+
if (task) {
files = get_files_struct(task);
if (files) {
@@ -2045,7 +2058,7 @@ static struct dentry *proc_fd_instantiate(struct inode *dir,
inode->i_op = &proc_pid_link_inode_operations;
inode->i_size = 64;
ei->op.proc_get_link = proc_fd_link;
- dentry->d_op = &tid_fd_dentry_operations;
+ d_set_d_op(dentry, &tid_fd_dentry_operations);
d_add(dentry, inode);
/* Close the race of the process dying before we return the dentry */
if (tid_fd_revalidate(dentry, NULL))
@@ -2177,11 +2190,13 @@ static const struct file_operations proc_fd_operations = {
* /proc/pid/fd needs a special permission handler so that a process can still
* access /proc/self/fd after it has executed a setuid().
*/
-static int proc_fd_permission(struct inode *inode, int mask)
+static int proc_fd_permission(struct inode *inode, int mask, unsigned int flags)
{
int rv;
- rv = generic_permission(inode, mask, NULL);
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+ rv = generic_permission(inode, mask, flags, NULL);
if (rv == 0)
return 0;
if (task_pid(current) == proc_pid(inode))
@@ -2213,7 +2228,7 @@ static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
ei->fd = fd;
inode->i_mode = S_IFREG | S_IRUSR;
inode->i_fop = &proc_fdinfo_file_operations;
- dentry->d_op = &tid_fd_dentry_operations;
+ d_set_d_op(dentry, &tid_fd_dentry_operations);
d_add(dentry, inode);
/* Close the race of the process dying before we return the dentry */
if (tid_fd_revalidate(dentry, NULL))
@@ -2272,7 +2287,7 @@ static struct dentry *proc_pident_instantiate(struct inode *dir,
if (p->fop)
inode->i_fop = p->fop;
ei->op = p->op;
- dentry->d_op = &pid_dentry_operations;
+ d_set_d_op(dentry, &pid_dentry_operations);
d_add(dentry, inode);
/* Close the race of the process dying before we return the dentry */
if (pid_revalidate(dentry, NULL))
@@ -2639,8 +2654,14 @@ static const struct pid_entry proc_base_stuff[] = {
*/
static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct inode *inode = dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
+ struct inode *inode;
+ struct task_struct *task;
+
+ if (nd->flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ inode = dentry->d_inode;
+ task = get_proc_task(inode);
if (task) {
put_task_struct(task);
return 1;
@@ -2691,7 +2712,7 @@ static struct dentry *proc_base_instantiate(struct inode *dir,
if (p->fop)
inode->i_fop = p->fop;
ei->op = p->op;
- dentry->d_op = &proc_base_dentry_operations;
+ d_set_d_op(dentry, &proc_base_dentry_operations);
d_add(dentry, inode);
error = NULL;
out:
@@ -3005,7 +3026,7 @@ static struct dentry *proc_pid_instantiate(struct inode *dir,
inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
ARRAY_SIZE(tgid_base_stuff));
- dentry->d_op = &pid_dentry_operations;
+ d_set_d_op(dentry, &pid_dentry_operations);
d_add(dentry, inode);
/* Close the race of the process dying before we return the dentry */
@@ -3248,7 +3269,7 @@ static struct dentry *proc_task_instantiate(struct inode *dir,
inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
ARRAY_SIZE(tid_base_stuff));
- dentry->d_op = &pid_dentry_operations;
+ d_set_d_op(dentry, &pid_dentry_operations);
d_add(dentry, inode);
/* Close the race of the process dying before we return the dentry */
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index dd29f0337661..f766be29d2c7 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -400,7 +400,7 @@ static const struct inode_operations proc_link_inode_operations = {
* smarter: we could keep a "volatile" flag in the
* inode to indicate which ones to keep.
*/
-static int proc_delete_dentry(struct dentry * dentry)
+static int proc_delete_dentry(const struct dentry * dentry)
{
return 1;
}
@@ -439,7 +439,7 @@ struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir,
out_unlock:
if (inode) {
- dentry->d_op = &proc_dentry_operations;
+ d_set_d_op(dentry, &proc_dentry_operations);
d_add(dentry, inode);
return NULL;
}
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 3ddb6068177c..6bcb926b101b 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -65,11 +65,18 @@ static struct inode *proc_alloc_inode(struct super_block *sb)
return inode;
}
-static void proc_destroy_inode(struct inode *inode)
+static void proc_i_callback(struct rcu_head *head)
{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ INIT_LIST_HEAD(&inode->i_dentry);
kmem_cache_free(proc_inode_cachep, PROC_I(inode));
}
+static void proc_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, proc_i_callback);
+}
+
static void init_once(void *foo)
{
struct proc_inode *ei = (struct proc_inode *) foo;
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index b652cb00906b..09a1f92a34ef 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -5,6 +5,7 @@
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/security.h>
+#include <linux/namei.h>
#include "internal.h"
static const struct dentry_operations proc_sys_dentry_operations;
@@ -120,7 +121,7 @@ static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry,
goto out;
err = NULL;
- dentry->d_op = &proc_sys_dentry_operations;
+ d_set_d_op(dentry, &proc_sys_dentry_operations);
d_add(dentry, inode);
out:
@@ -201,7 +202,7 @@ static int proc_sys_fill_cache(struct file *filp, void *dirent,
dput(child);
return -ENOMEM;
} else {
- child->d_op = &proc_sys_dentry_operations;
+ d_set_d_op(child, &proc_sys_dentry_operations);
d_add(child, inode);
}
} else {
@@ -294,7 +295,7 @@ out:
return ret;
}
-static int proc_sys_permission(struct inode *inode, int mask)
+static int proc_sys_permission(struct inode *inode, int mask,unsigned int flags)
{
/*
* sysctl entries that are not writeable,
@@ -304,6 +305,9 @@ static int proc_sys_permission(struct inode *inode, int mask)
struct ctl_table *table;
int error;
+ if (flags & IPERM_FLAG_RCU)
+ return -ECHILD;
+
/* Executable files are not allowed under /proc/sys/ */
if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))
return -EACCES;
@@ -389,23 +393,30 @@ static const struct inode_operations proc_sys_dir_operations = {
static int proc_sys_revalidate(struct dentry *dentry, struct nameidata *nd)
{
+ if (nd->flags & LOOKUP_RCU)
+ return -ECHILD;
return !PROC_I(dentry->d_inode)->sysctl->unregistering;
}
-static int proc_sys_delete(struct dentry *dentry)
+static int proc_sys_delete(const struct dentry *dentry)
{
return !!PROC_I(dentry->d_inode)->sysctl->unregistering;
}
-static int proc_sys_compare(struct dentry *dir, struct qstr *qstr,
- struct qstr *name)
+static int proc_sys_compare(const struct dentry *parent,
+ const struct inode *pinode,
+ const struct dentry *dentry, const struct inode *inode,
+ unsigned int len, const char *str, const struct qstr *name)
{
- struct dentry *dentry = container_of(qstr, struct dentry, d_name);
- if (qstr->len != name->len)
+ /* Although proc doesn't have negative dentries, rcu-walk means
+ * that inode here can be NULL */
+ if (!inode)
+ return 0;
+ if (name->len != len)
return 1;
- if (memcmp(qstr->name, name->name, name->len))
+ if (memcmp(name->name, str, len))
return 1;
- return !sysctl_is_seen(PROC_I(dentry->d_inode)->sysctl);
+ return !sysctl_is_seen(PROC_I(inode)->sysctl);
}
static const struct dentry_operations proc_sys_dentry_operations = {