diff options
| -rw-r--r-- | fs/proc/Makefile | 2 | ||||
| -rw-r--r-- | fs/proc/generic.c | 2 | ||||
| -rw-r--r-- | fs/proc/inode.c | 1 | ||||
| -rw-r--r-- | fs/proc/internal.h | 2 | ||||
| -rw-r--r-- | fs/proc/proc_sysctl.c | 478 | ||||
| -rw-r--r-- | fs/proc/root.c | 10 | ||||
| -rw-r--r-- | include/linux/proc_fs.h | 2 | ||||
| -rw-r--r-- | include/linux/sysctl.h | 2 | ||||
| -rw-r--r-- | init/main.c | 4 | ||||
| -rw-r--r-- | kernel/sysctl.c | 182 |
10 files changed, 486 insertions, 199 deletions
diff --git a/fs/proc/Makefile b/fs/proc/Makefile index f6c7762..a6b3a8f 100644 --- a/fs/proc/Makefile +++ b/fs/proc/Makefile @@ -8,7 +8,7 @@ proc-y := nommu.o task_nommu.o proc-$(CONFIG_MMU) := mmu.o task_mmu.o proc-y += inode.o root.o base.o generic.o array.o \ - proc_tty.o proc_misc.o + proc_tty.o proc_misc.o proc_sysctl.o proc-$(CONFIG_PROC_KCORE) += kcore.o proc-$(CONFIG_PROC_VMCORE) += vmcore.o diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 0cdc00d..775fb21 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -32,7 +32,7 @@ static loff_t proc_file_lseek(struct file *, loff_t, int); DEFINE_SPINLOCK(proc_subdir_lock); -int proc_match(int len, const char *name, struct proc_dir_entry *de) +static int proc_match(int len, const char *name, struct proc_dir_entry *de) { if (de->namelen != len) return 0; diff --git a/fs/proc/inode.c b/fs/proc/inode.c index f6722be..c372eb15 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -161,6 +161,7 @@ struct inode *proc_get_inode(struct super_block *sb, unsigned int ino, if (!inode) goto out_ino; + PROC_I(inode)->fd = 0; PROC_I(inode)->pde = de; if (de) { if (de->mode) { diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 277dcd6..c932aa6 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -11,6 +11,8 @@ #include <linux/proc_fs.h> +extern int proc_sys_init(void); + struct vmalloc_info { unsigned long used; unsigned long largest_chunk; diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c new file mode 100644 index 0000000..bb16a1e --- /dev/null +++ b/fs/proc/proc_sysctl.c @@ -0,0 +1,478 @@ +/* + * /proc/sys support + */ + +#include <linux/sysctl.h> +#include <linux/proc_fs.h> +#include <linux/security.h> +#include "internal.h" + +static struct dentry_operations proc_sys_dentry_operations; +static const struct file_operations proc_sys_file_operations; +static struct inode_operations proc_sys_inode_operations; + +static void proc_sys_refresh_inode(struct inode *inode, struct ctl_table *table) +{ + /* Refresh the cached information bits in the inode */ + if (table) { + inode->i_uid = 0; + inode->i_gid = 0; + inode->i_mode = table->mode; + if (table->proc_handler) { + inode->i_mode |= S_IFREG; + inode->i_nlink = 1; + } else { + inode->i_mode |= S_IFDIR; + inode->i_nlink = 0; /* It is too hard to figure out */ + } + } +} + +static struct inode *proc_sys_make_inode(struct inode *dir, struct ctl_table *table) +{ + struct inode *inode; + struct proc_inode *dir_ei, *ei; + int depth; + + inode = new_inode(dir->i_sb); + if (!inode) + goto out; + + /* A directory is always one deeper than it's parent */ + dir_ei = PROC_I(dir); + depth = dir_ei->fd + 1; + + ei = PROC_I(inode); + ei->fd = depth; + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; + inode->i_op = &proc_sys_inode_operations; + inode->i_fop = &proc_sys_file_operations; + proc_sys_refresh_inode(inode, table); +out: + return inode; +} + +static struct dentry *proc_sys_ancestor(struct dentry *dentry, int depth) +{ + for (;;) { + struct proc_inode *ei; + + ei = PROC_I(dentry->d_inode); + if (ei->fd == depth) + break; /* found */ + + dentry = dentry->d_parent; + } + return dentry; +} + +static struct ctl_table *proc_sys_lookup_table_one(struct ctl_table *table, + struct qstr *name) +{ + int len; + for ( ; table->ctl_name || table->procname; table++) { + + if (!table->procname) + continue; + + len = strlen(table->procname); + if (len != name->len) + continue; + + if (memcmp(table->procname, name->name, len) != 0) + continue; + + /* I have a match */ + return table; + } + return NULL; +} + +static struct ctl_table *proc_sys_lookup_table(struct dentry *dentry, + struct ctl_table *table) +{ + struct dentry *ancestor; + struct proc_inode *ei; + int depth, i; + + ei = PROC_I(dentry->d_inode); + depth = ei->fd; + + if (depth == 0) + return table; + + for (i = 1; table && (i <= depth); i++) { + ancestor = proc_sys_ancestor(dentry, i); + table = proc_sys_lookup_table_one(table, &ancestor->d_name); + if (table) + table = table->child; + } + return table; + +} +static struct ctl_table *proc_sys_lookup_entry(struct dentry *dparent, + struct qstr *name, + struct ctl_table *table) +{ + table = proc_sys_lookup_table(dparent, table); + if (table) + table = proc_sys_lookup_table_one(table, name); + return table; +} + +static struct ctl_table *do_proc_sys_lookup(struct dentry *parent, + struct qstr *name, + struct ctl_table_header **ptr) +{ + struct ctl_table_header *head; + struct ctl_table *table = NULL; + + for (head = sysctl_head_next(NULL); head; + head = sysctl_head_next(head)) { + table = proc_sys_lookup_entry(parent, name, head->ctl_table); + if (table) + break; + } + *ptr = head; + return table; +} + +static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry, + struct nameidata *nd) +{ + struct ctl_table_header *head; + struct inode *inode; + struct dentry *err; + struct ctl_table *table; + + err = ERR_PTR(-ENOENT); + table = do_proc_sys_lookup(dentry->d_parent, &dentry->d_name, &head); + if (!table) + goto out; + + err = ERR_PTR(-ENOMEM); + inode = proc_sys_make_inode(dir, table); + if (!inode) + goto out; + + err = NULL; + dentry->d_op = &proc_sys_dentry_operations; + d_add(dentry, inode); + +out: + sysctl_head_finish(head); + return err; +} + +static ssize_t proc_sys_read(struct file *filp, char __user *buf, + size_t count, loff_t *ppos) +{ + struct dentry *dentry = filp->f_dentry; + struct ctl_table_header *head; + struct ctl_table *table; + ssize_t error, res; + + table = do_proc_sys_lookup(dentry->d_parent, &dentry->d_name, &head); + /* Has the sysctl entry disappeared on us? */ + error = -ENOENT; + if (!table) + goto out; + + /* Has the sysctl entry been replaced by a directory? */ + error = -EISDIR; + if (!table->proc_handler) + goto out; + + /* + * At this point we know that the sysctl was not unregistered + * and won't be until we finish. + */ + error = -EPERM; + if (sysctl_perm(table, MAY_READ)) + goto out; + + /* careful: calling conventions are nasty here */ + res = count; + error = table->proc_handler(table, 0, filp, buf, &res, ppos); + if (!error) + error = res; +out: + sysctl_head_finish(head); + + return error; +} + +static ssize_t proc_sys_write(struct file *filp, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct dentry *dentry = filp->f_dentry; + struct ctl_table_header *head; + struct ctl_table *table; + ssize_t error, res; + + table = do_proc_sys_lookup(dentry->d_parent, &dentry->d_name, &head); + /* Has the sysctl entry disappeared on us? */ + error = -ENOENT; + if (!table) + goto out; + + /* Has the sysctl entry been replaced by a directory? */ + error = -EISDIR; + if (!table->proc_handler) + goto out; + + /* + * At this point we know that the sysctl was not unregistered + * and won't be until we finish. + */ + error = -EPERM; + if (sysctl_perm(table, MAY_WRITE)) + goto out; + + /* careful: calling conventions are nasty here */ + res = count; + error = table->proc_handler(table, 1, filp, (char __user *)buf, + &res, ppos); + if (!error) + error = res; +out: + sysctl_head_finish(head); + + return error; +} + + +static int proc_sys_fill_cache(struct file *filp, void *dirent, + filldir_t filldir, struct ctl_table *table) +{ + struct ctl_table_header *head; + struct ctl_table *child_table = NULL; + struct dentry *child, *dir = filp->f_path.dentry; + struct inode *inode; + struct qstr qname; + ino_t ino = 0; + unsigned type = DT_UNKNOWN; + int ret; + + qname.name = table->procname; + qname.len = strlen(table->procname); + qname.hash = full_name_hash(qname.name, qname.len); + + /* Suppress duplicates. + * Only fill a directory entry if it is the value that + * an ordinary lookup of that name returns. Hide all + * others. + * + * If we ever cache this translation in the dcache + * I should do a dcache lookup first. But for now + * it is just simpler not to. + */ + ret = 0; + child_table = do_proc_sys_lookup(dir, &qname, &head); + sysctl_head_finish(head); + if (child_table != table) + return 0; + + child = d_lookup(dir, &qname); + if (!child) { + struct dentry *new; + new = d_alloc(dir, &qname); + if (new) { + inode = proc_sys_make_inode(dir->d_inode, table); + if (!inode) + child = ERR_PTR(-ENOMEM); + else { + new->d_op = &proc_sys_dentry_operations; + d_add(new, inode); + } + if (child) + dput(new); + else + child = new; + } + } + if (!child || IS_ERR(child) || !child->d_inode) + goto end_instantiate; + inode = child->d_inode; + if (inode) { + ino = inode->i_ino; + type = inode->i_mode >> 12; + } + dput(child); +end_instantiate: + if (!ino) + ino= find_inode_number(dir, &qname); + if (!ino) + ino = 1; + return filldir(dirent, qname.name, qname.len, filp->f_pos, ino, type); +} + +static int proc_sys_readdir(struct file *filp, void *dirent, filldir_t filldir) +{ + struct dentry *dentry = filp->f_dentry; + struct inode *inode = dentry->d_inode; + struct ctl_table_header *head = NULL; + struct ctl_table *table; + unsigned long pos; + int ret; + + ret = -ENOTDIR; + if (!S_ISDIR(inode->i_mode)) + goto out; + + ret = 0; + /* Avoid a switch here: arm builds fail with missing __cmpdi2 */ + if (filp->f_pos == 0) { + if (filldir(dirent, ".", 1, filp->f_pos, + inode->i_ino, DT_DIR) < 0) + goto out; + filp->f_pos++; + } + if (filp->f_pos == 1) { + if (filldir(dirent, "..", 2, filp->f_pos, + parent_ino(dentry), DT_DIR) < 0) + goto out; + filp->f_pos++; + } + pos = 2; + + /* - Find each instance of the directory + * - Read all entries in each instance + * - Before returning an entry to user space lookup the entry + * by name and if I find a different entry don't return + * this one because it means it is a buried dup. + * For sysctl this should only happen for directory entries. + */ + for (head = sysctl_head_next(NULL); head; head = sysctl_head_next(head)) { + table = proc_sys_lookup_table(dentry, head->ctl_table); + + if (!table) + continue; + + for (; table->ctl_name || table->procname; table++, pos++) { + /* Can't do anything without a proc name */ + if (!table->procname) + continue; + + if (pos < filp->f_pos) + continue; + + if (proc_sys_fill_cache(filp, dirent, filldir, table) < 0) + goto out; + filp->f_pos = pos + 1; + } + } + ret = 1; +out: + sysctl_head_finish(head); + return ret; +} + +static int proc_sys_permission(struct inode *inode, int mask, struct nameidata *nd) +{ + /* + * sysctl entries that are not writeable, + * are _NOT_ writeable, capabilities or not. + */ + struct ctl_table_header *head; + struct ctl_table *table; + struct dentry *dentry; + int mode; + int depth; + int error; + + head = NULL; + depth = PROC_I(inode)->fd; + + /* First check the cached permissions, in case we don't have + * enough information to lookup the sysctl table entry. + */ + error = -EACCES; + mode = inode->i_mode; + + if (current->euid == 0) + mode >>= 6; + else if (in_group_p(0)) + mode >>= 3; + + if ((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask) + error = 0; + + /* If we can't get a sysctl table entry the permission + * checks on the cached mode will have to be enough. + */ + if (!nd || !depth) + goto out; + + dentry = nd->dentry; + table = do_proc_sys_lookup(dentry->d_parent, &dentry->d_name, &head); + + /* If the entry does not exist deny permission */ + error = -EACCES; + if (!table) + goto out; + + /* Use the permissions on the sysctl table entry */ + error = sysctl_perm(table, mask); +out: + sysctl_head_finish(head); + return error; +} + +static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr) +{ + struct inode *inode = dentry->d_inode; + int error; + + if (attr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) + return -EPERM; + + error = inode_change_ok(inode, attr); + if (!error) { + error = security_inode_setattr(dentry, attr); + if (!error) + error = inode_setattr(inode, attr); + } + + return error; +} + +/* I'm lazy and don't distinguish between files and directories, + * until access time. + */ +static const struct file_operations proc_sys_file_operations = { + .read = proc_sys_read, + .write = proc_sys_write, + .readdir = proc_sys_readdir, +}; + +static struct inode_operations proc_sys_inode_operations = { + .lookup = proc_sys_lookup, + .permission = proc_sys_permission, + .setattr = proc_sys_setattr, +}; + +static int proc_sys_revalidate(struct dentry *dentry, struct nameidata *nd) +{ + struct ctl_table_header *head; + struct ctl_table *table; + table = do_proc_sys_lookup(dentry->d_parent, &dentry->d_name, &head); + proc_sys_refresh_inode(dentry->d_inode, table); + sysctl_head_finish(head); + return !!table; +} + +static struct dentry_operations proc_sys_dentry_operations = { + .d_revalidate = proc_sys_revalidate, +}; + +static struct proc_dir_entry *proc_sys_root; + +int proc_sys_init(void) +{ + proc_sys_root = proc_mkdir("sys", NULL); + proc_sys_root->proc_iops = &proc_sys_inode_operations; + proc_sys_root->proc_fops = &proc_sys_file_operations; + proc_sys_root->nlink = 0; + return 0; +} diff --git a/fs/proc/root.c b/fs/proc/root.c index 6ae222b..5834a744 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -23,10 +23,6 @@ struct proc_dir_entry *proc_net, *proc_net_stat, *proc_bus, *proc_root_fs, *proc_root_driver; -#ifdef CONFIG_SYSCTL -struct proc_dir_entry *proc_sys_root; -#endif - static int proc_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, struct vfsmount *mnt) { @@ -71,9 +67,6 @@ void __init proc_root_init(void) #ifdef CONFIG_SYSVIPC proc_mkdir("sysvipc", NULL); #endif -#ifdef CONFIG_SYSCTL - proc_sys_root = proc_mkdir("sys", NULL); -#endif proc_root_fs = proc_mkdir("fs", NULL); proc_root_driver = proc_mkdir("driver", NULL); proc_mkdir("fs/nfsd", NULL); /* somewhere for the nfsd filesystem to be mounted */ @@ -86,6 +79,9 @@ void __init proc_root_init(void) proc_device_tree_init(); #endif proc_bus = proc_mkdir("bus", NULL); +#ifdef CONFIG_SYSCTL + proc_sys_init(); +#endif } static int proc_root_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index 2e13247..be4652a 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -113,8 +113,6 @@ extern struct vfsmount *proc_mnt; extern int proc_fill_super(struct super_block *,void *,int); extern struct inode *proc_get_inode(struct super_block *, unsigned int, struct proc_dir_entry *); -extern int proc_match(int, const char *,struct proc_dir_entry *); - /* * These are generic /proc routines that use the internal * "struct proc_dir_entry" tree to traverse the filesystem. diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h index 9698ac3..8915049 100644 --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -930,8 +930,6 @@ extern struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev); extern void sysctl_head_finish(struct ctl_table_header *prev); extern int sysctl_perm(struct ctl_table *table, int op); -extern void sysctl_init(void); - typedef struct ctl_table ctl_table; typedef int ctl_handler (ctl_table *table, int __user *name, int nlen, diff --git a/init/main.c b/init/main.c index a20a513..649ab54 100644 --- a/init/main.c +++ b/init/main.c @@ -86,7 +86,6 @@ extern void init_IRQ(void); extern void fork_init(unsigned long); extern void mca_init(void); extern void sbus_init(void); -extern void sysctl_init(void); extern void signals_init(void); extern void pidhash_init(void); extern void pidmap_init(void); @@ -702,9 +701,6 @@ static void __init do_basic_setup(void) usermodehelper_init(); driver_init(); -#ifdef CONFIG_SYSCTL - sysctl_init(); -#endif #ifdef CONFIG_PROC_FS init_irq_proc(); #endif diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 6bbac5c..b3ee791 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -159,26 +159,6 @@ int sysctl_legacy_va_layout; #endif -/* /proc declarations: */ - -#ifdef CONFIG_PROC_SYSCTL - -static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *); -static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *); -static int proc_opensys(struct inode *, struct file *); - -const struct file_operations proc_sys_file_operations = { - .open = proc_opensys, - .read = proc_readsys, - .write = proc_writesys, -}; - -extern struct proc_dir_entry *proc_sys_root; - -static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *); -static void unregister_proc_table(ctl_table *, struct proc_dir_entry *); -#endif - /* The default sysctl tables: */ static ctl_table root_table[] = { @@ -1106,13 +1086,6 @@ struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) return NULL; } -void __init sysctl_init(void) -{ -#ifdef CONFIG_PROC_SYSCTL - register_proc_table(root_table, proc_sys_root, &root_table_header); -#endif -} - #ifdef CONFIG_SYSCTL_SYSCALL int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen) @@ -1348,9 +1321,6 @@ struct ctl_table_header *register_sysctl_table(ctl_table * table) spin_lock(&sysctl_lock); list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); spin_unlock(&sysctl_lock); -#ifdef CONFIG_PROC_SYSCTL - register_proc_table(table, proc_sys_root, tmp); -#endif return tmp; } @@ -1366,9 +1336,6 @@ void unregister_sysctl_table(struct ctl_table_header * header) might_sleep(); spin_lock(&sysctl_lock); start_unregistering(header); -#ifdef CONFIG_PROC_SYSCTL - unregister_proc_table(header->ctl_table, proc_sys_root); -#endif spin_unlock(&sysctl_lock); kfree(header); } @@ -1392,155 +1359,6 @@ void unregister_sysctl_table(struct ctl_table_header * table) #ifdef CONFIG_PROC_SYSCTL -/* Scan the sysctl entries in table and add them all into /proc */ -static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set) -{ - struct proc_dir_entry *de; - int len; - mode_t mode; - - for (; table->ctl_name || table->procname; table++) { - /* Can't do anything without a proc name. */ - if (!table->procname) - continue; - /* Maybe we can't do anything with it... */ - if (!table->proc_handler && !table->child) { - printk(KERN_WARNING "SYSCTL: Can't register %s\n", - table->procname); - continue; - } - - len = strlen(table->procname); - mode = table->mode; - - de = NULL; - if (table->proc_handler) - mode |= S_IFREG; - else { - mode |= S_IFDIR; - for (de = root->subdir; de; de = de->next) { - if (proc_match(len, table->procname, de)) - break; - } - /* If the subdir exists already, de is non-NULL */ - } - - if (!de) { - de = create_proc_entry(table->procname, mode, root); - if (!de) - continue; - de->set = set; - de->data = (void *) table; - if (table->proc_handler) - de->proc_fops = &proc_sys_file_operations; - } - table->de = de; - if (de->mode & S_IFDIR) - register_proc_table(table->child, de, set); - } -} - -/* - * Unregister a /proc sysctl table and any subdirectories. - */ -static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root) -{ - struct proc_dir_entry *de; - for (; table->ctl_name || table->procname; table++) { - if (!(de = table->de)) - continue; - if (de->mode & S_IFDIR) { - if (!table->child) { - printk (KERN_ALERT "Help - malformed sysctl tree on free\n"); - continue; - } - unregister_proc_table(table->child, de); - - /* Don't unregister directories which still have entries.. */ - if (de->subdir) - continue; - } - - /* - * In any case, mark the entry as goner; we'll keep it - * around if it's busy, but we'll know to do nothing with - * its fields. We are under sysctl_lock here. - */ - de->data = NULL; - - /* Don't unregister proc entries that are still being used.. */ - if (atomic_read(&de->count)) - continue; - - table->de = NULL; - remove_proc_entry(table->procname, root); - } -} - -static ssize_t do_rw_proc(int write, struct file * file, char __user * buf, - size_t count, loff_t *ppos) -{ - int op; - struct proc_dir_entry *de = PDE(file->f_path.dentry->d_inode); - struct ctl_table *table; - size_t res; - ssize_t error = -ENOTDIR; - - spin_lock(&sysctl_lock); - if (de && de->data && use_table(de->set)) { - /* - * at that point we know that sysctl was not unregistered - * and won't be until we finish - */ - spin_unlock(&sysctl_lock); - table = (struct ctl_table *) de->data; - if (!table || !table->proc_handler) - goto out; - error = -EPERM; - op = (write ? 002 : 004); - if (sysctl_perm(table, op)) - goto out; - - /* careful: calling conventions are nasty here */ - res = count; - error = (*table->proc_handler)(table, write, file, - buf, &res, ppos); - if (!error) - error = res; - out: - spin_lock(&sysctl_lock); - unuse_table(de->set); - } - spin_unlock(&sysctl_lock); - return error; -} - -static int proc_opensys(struct inode *inode, struct file *file) -{ - if (file->f_mode & FMODE_WRITE) { - /* - * sysctl entries that are not writable, - * are _NOT_ writable, capabilities or not. - */ - if (!(inode->i_mode & S_IWUSR)) - return -EPERM; - } - - return 0; -} - -static ssize_t proc_readsys(struct file * file, char __user * buf, - size_t count, loff_t *ppos) -{ - return do_rw_proc(0, file, buf, count, ppos); -} - -static ssize_t proc_writesys(struct file * file, const char __user * buf, - size_t count, loff_t *ppos) -{ - return do_rw_proc(1, file, (char __user *) buf, count, ppos); -} - static int _proc_do_string(void* data, int maxlen, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) |
