diff options
Diffstat (limited to 'fs/proc')
-rw-r--r-- | fs/proc/base.c | 53 | ||||
-rw-r--r-- | fs/proc/generic.c | 4 | ||||
-rw-r--r-- | fs/proc/inode.c | 9 | ||||
-rw-r--r-- | fs/proc/proc_sysctl.c | 31 |
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 = { |