diff options
| -rw-r--r-- | fs/exec.c | 10 | ||||
| -rw-r--r-- | fs/namei.c | 143 | ||||
| -rw-r--r-- | fs/open.c | 10 | ||||
| -rw-r--r-- | include/linux/audit.h | 3 | ||||
| -rw-r--r-- | include/linux/fs.h | 9 | ||||
| -rw-r--r-- | kernel/audit.h | 17 | ||||
| -rw-r--r-- | kernel/auditsc.c | 171 |
7 files changed, 145 insertions, 218 deletions
diff --git a/fs/exec.c b/fs/exec.c index ad8798e26be9..c7f9b733406d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -794,8 +794,14 @@ exit: struct file *open_exec(const char *name) { - struct filename tmp = { .name = name }; - return do_open_execat(AT_FDCWD, &tmp, 0); + struct filename *filename = getname_kernel(name); + struct file *f = ERR_CAST(filename); + + if (!IS_ERR(filename)) { + f = do_open_execat(AT_FDCWD, filename, 0); + putname(filename); + } + return f; } EXPORT_SYMBOL(open_exec); diff --git a/fs/namei.c b/fs/namei.c index bc35b02883bb..96ca11dea4a2 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -118,15 +118,6 @@ * POSIX.1 2.4: an empty pathname is invalid (ENOENT). * PATH_MAX includes the nul terminator --RR. */ -void final_putname(struct filename *name) -{ - if (name->separate) { - __putname(name->name); - kfree(name); - } else { - __putname(name); - } -} #define EMBEDDED_NAME_MAX (PATH_MAX - sizeof(struct filename)) @@ -145,6 +136,7 @@ getname_flags(const char __user *filename, int flags, int *empty) result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); + result->refcnt = 1; /* * First, try to embed the struct filename inside the names_cache @@ -179,6 +171,7 @@ recopy: } result->name = kname; result->separate = true; + result->refcnt = 1; max = PATH_MAX; goto recopy; } @@ -202,7 +195,7 @@ recopy: return result; error: - final_putname(result); + putname(result); return err; } @@ -212,43 +205,56 @@ getname(const char __user * filename) return getname_flags(filename, 0, NULL); } -/* - * The "getname_kernel()" interface doesn't do pathnames longer - * than EMBEDDED_NAME_MAX. Deal with it - you're a kernel user. - */ struct filename * getname_kernel(const char * filename) { struct filename *result; - char *kname; - int len; - - len = strlen(filename); - if (len >= EMBEDDED_NAME_MAX) - return ERR_PTR(-ENAMETOOLONG); + int len = strlen(filename) + 1; result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); - kname = (char *)result + sizeof(*result); - result->name = kname; + if (len <= EMBEDDED_NAME_MAX) { + result->name = (char *)(result) + sizeof(*result); + result->separate = false; + } else if (len <= PATH_MAX) { + struct filename *tmp; + + tmp = kmalloc(sizeof(*tmp), GFP_KERNEL); + if (unlikely(!tmp)) { + __putname(result); + return ERR_PTR(-ENOMEM); + } + tmp->name = (char *)result; + tmp->separate = true; + result = tmp; + } else { + __putname(result); + return ERR_PTR(-ENAMETOOLONG); + } + memcpy((char *)result->name, filename, len); result->uptr = NULL; result->aname = NULL; - result->separate = false; + result->refcnt = 1; + audit_getname(result); - strlcpy(kname, filename, EMBEDDED_NAME_MAX); return result; } -#ifdef CONFIG_AUDITSYSCALL void putname(struct filename *name) { - if (unlikely(!audit_dummy_context())) - return audit_putname(name); - final_putname(name); + BUG_ON(name->refcnt <= 0); + + if (--name->refcnt > 0) + return; + + if (name->separate) { + __putname(name->name); + kfree(name); + } else + __putname(name); } -#endif static int check_acl(struct inode *inode, int mask) { @@ -2036,31 +2042,47 @@ static int filename_lookup(int dfd, struct filename *name, static int do_path_lookup(int dfd, const char *name, unsigned int flags, struct nameidata *nd) { - struct filename filename = { .name = name }; + struct filename *filename = getname_kernel(name); + int retval = PTR_ERR(filename); - return filename_lookup(dfd, &filename, flags, nd); + if (!IS_ERR(filename)) { + retval = filename_lookup(dfd, filename, flags, nd); + putname(filename); + } + return retval; } /* does lookup, returns the object with parent locked */ struct dentry *kern_path_locked(const char *name, struct path *path) { + struct filename *filename = getname_kernel(name); struct nameidata nd; struct dentry *d; - int err = do_path_lookup(AT_FDCWD, name, LOOKUP_PARENT, &nd); - if (err) - return ERR_PTR(err); + int err; + + if (IS_ERR(filename)) + return ERR_CAST(filename); + + err = filename_lookup(AT_FDCWD, filename, LOOKUP_PARENT, &nd); + if (err) { + d = ERR_PTR(err); + goto out; + } if (nd.last_type != LAST_NORM) { path_put(&nd.path); - return ERR_PTR(-EINVAL); + d = ERR_PTR(-EINVAL); + goto out; } mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); d = __lookup_hash(&nd.last, nd.path.dentry, 0); if (IS_ERR(d)) { mutex_unlock(&nd.path.dentry->d_inode->i_mutex); path_put(&nd.path); - return d; + goto out; } *path = nd.path; +out: + putname(filename); return d; } @@ -2351,13 +2373,17 @@ static int filename_mountpoint(int dfd, struct filename *s, struct path *path, unsigned int flags) { - int error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU); + int error; + if (IS_ERR(s)) + return PTR_ERR(s); + error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU); if (unlikely(error == -ECHILD)) error = path_mountpoint(dfd, s->name, path, flags); if (unlikely(error == -ESTALE)) error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_REVAL); if (likely(!error)) audit_inode(s, path->dentry, 0); + putname(s); return error; } @@ -2379,21 +2405,14 @@ int user_path_mountpoint_at(int dfd, const char __user *name, unsigned int flags, struct path *path) { - struct filename *s = getname(name); - int error; - if (IS_ERR(s)) - return PTR_ERR(s); - error = filename_mountpoint(dfd, s, path, flags); - putname(s); - return error; + return filename_mountpoint(dfd, getname(name), path, flags); } int kern_path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags) { - struct filename s = {.name = name}; - return filename_mountpoint(dfd, &s, path, flags); + return filename_mountpoint(dfd, getname_kernel(name), path, flags); } EXPORT_SYMBOL(kern_path_mountpoint); @@ -3273,7 +3292,7 @@ struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, { struct nameidata nd; struct file *file; - struct filename filename = { .name = name }; + struct filename *filename; int flags = op->lookup_flags | LOOKUP_ROOT; nd.root.mnt = mnt; @@ -3282,15 +3301,20 @@ struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, if (d_is_symlink(dentry) && op->intent & LOOKUP_OPEN) return ERR_PTR(-ELOOP); - file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_RCU); + filename = getname_kernel(name); + if (unlikely(IS_ERR(filename))) + return ERR_CAST(filename); + + file = path_openat(-1, filename, &nd, op, flags | LOOKUP_RCU); if (unlikely(file == ERR_PTR(-ECHILD))) - file = path_openat(-1, &filename, &nd, op, flags); + file = path_openat(-1, filename, &nd, op, flags); if (unlikely(file == ERR_PTR(-ESTALE))) - file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_REVAL); + file = path_openat(-1, filename, &nd, op, flags | LOOKUP_REVAL); + putname(filename); return file; } -struct dentry *kern_path_create(int dfd, const char *pathname, +static struct dentry *filename_create(int dfd, struct filename *name, struct path *path, unsigned int lookup_flags) { struct dentry *dentry = ERR_PTR(-EEXIST); @@ -3305,7 +3329,7 @@ struct dentry *kern_path_create(int dfd, const char *pathname, */ lookup_flags &= LOOKUP_REVAL; - error = do_path_lookup(dfd, pathname, LOOKUP_PARENT|lookup_flags, &nd); + error = filename_lookup(dfd, name, LOOKUP_PARENT|lookup_flags, &nd); if (error) return ERR_PTR(error); @@ -3359,6 +3383,19 @@ out: path_put(&nd.path); return dentry; } + +struct dentry *kern_path_create(int dfd, const char *pathname, + struct path *path, unsigned int lookup_flags) +{ + struct filename *filename = getname_kernel(pathname); + struct dentry *res; + + if (IS_ERR(filename)) + return ERR_CAST(filename); + res = filename_create(dfd, filename, path, lookup_flags); + putname(filename); + return res; +} EXPORT_SYMBOL(kern_path_create); void done_path_create(struct path *path, struct dentry *dentry) @@ -3377,7 +3414,7 @@ struct dentry *user_path_create(int dfd, const char __user *pathname, struct dentry *res; if (IS_ERR(tmp)) return ERR_CAST(tmp); - res = kern_path_create(dfd, tmp->name, path, lookup_flags); + res = filename_create(dfd, tmp, path, lookup_flags); putname(tmp); return res; } diff --git a/fs/open.c b/fs/open.c index a293c2020676..33f9cbf2610b 100644 --- a/fs/open.c +++ b/fs/open.c @@ -968,8 +968,14 @@ struct file *file_open_name(struct filename *name, int flags, umode_t mode) */ struct file *filp_open(const char *filename, int flags, umode_t mode) { - struct filename name = {.name = filename}; - return file_open_name(&name, flags, mode); + struct filename *name = getname_kernel(filename); + struct file *file = ERR_CAST(name); + + if (!IS_ERR(name)) { + file = file_open_name(name, flags, mode); + putname(name); + } + return file; } EXPORT_SYMBOL(filp_open); diff --git a/include/linux/audit.h b/include/linux/audit.h index 599f3bd2d6c5..c2e7e3a83965 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -127,7 +127,6 @@ extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1, extern void __audit_syscall_exit(int ret_success, long ret_value); extern struct filename *__audit_reusename(const __user char *uptr); extern void __audit_getname(struct filename *name); -extern void audit_putname(struct filename *name); #define AUDIT_INODE_PARENT 1 /* dentry represents the parent */ #define AUDIT_INODE_HIDDEN 2 /* audit record should be hidden */ @@ -352,8 +351,6 @@ static inline struct filename *audit_reusename(const __user char *name) } static inline void audit_getname(struct filename *name) { } -static inline void audit_putname(struct filename *name) -{ } static inline void __audit_inode(struct filename *name, const struct dentry *dentry, unsigned int flags) diff --git a/include/linux/fs.h b/include/linux/fs.h index ed5a0900b94d..a9250b2a11ba 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2141,6 +2141,7 @@ struct filename { const char *name; /* pointer to actual string */ const __user char *uptr; /* original userland pointer */ struct audit_names *aname; + int refcnt; bool separate; /* should "name" be freed? */ }; @@ -2162,6 +2163,7 @@ extern int filp_close(struct file *, fl_owner_t id); extern struct filename *getname_flags(const char __user *, int, int *); extern struct filename *getname(const char __user *); extern struct filename *getname_kernel(const char *); +extern void putname(struct filename *name); enum { FILE_CREATED = 1, @@ -2182,15 +2184,8 @@ extern void __init vfs_caches_init(unsigned long); extern struct kmem_cache *names_cachep; -extern void final_putname(struct filename *name); - #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL) #define __putname(name) kmem_cache_free(names_cachep, (void *)(name)) -#ifndef CONFIG_AUDITSYSCALL -#define putname(name) final_putname(name) -#else -extern void putname(struct filename *name); -#endif #ifdef CONFIG_BLOCK extern int register_blkdev(unsigned int, const char *); diff --git a/kernel/audit.h b/kernel/audit.h index 3cdffad5a1d9..1caa0d345d90 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -24,12 +24,6 @@ #include <linux/skbuff.h> #include <uapi/linux/mqueue.h> -/* 0 = no checking - 1 = put_count checking - 2 = verbose put_count checking -*/ -#define AUDIT_DEBUG 0 - /* AUDIT_NAMES is the number of slots we reserve in the audit_context * for saving names from getname(). If we get more names we will allocate * a name dynamically and also add those to the list anchored by names_list. */ @@ -74,9 +68,8 @@ struct audit_cap_data { }; }; -/* When fs/namei.c:getname() is called, we store the pointer in name and - * we don't let putname() free it (instead we free all of the saved - * pointers at syscall exit time). +/* When fs/namei.c:getname() is called, we store the pointer in name and bump + * the refcnt in the associated filename struct. * * Further, in fs/namei.c:path_lookup() we store the inode and device. */ @@ -86,7 +79,6 @@ struct audit_names { struct filename *name; int name_len; /* number of chars to log */ bool hidden; /* don't log this record */ - bool name_put; /* call __putname()? */ unsigned long ino; dev_t dev; @@ -208,11 +200,6 @@ struct audit_context { }; int fds[2]; struct audit_proctitle proctitle; - -#if AUDIT_DEBUG - int put_count; - int ino_count; -#endif }; extern u32 audit_ever_enabled; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 55f82fce2526..dc4ae70a7413 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -866,33 +866,10 @@ static inline void audit_free_names(struct audit_context *context) { struct audit_names *n, *next; -#if AUDIT_DEBUG == 2 - if (context->put_count + context->ino_count != context->name_count) { - int i = 0; - - pr_err("%s:%d(:%d): major=%d in_syscall=%d" - " name_count=%d put_count=%d ino_count=%d" - " [NOT freeing]\n", __FILE__, __LINE__, - context->serial, context->major, context->in_syscall, - context->name_count, context->put_count, - context->ino_count); - list_for_each_entry(n, &context->names_list, list) { - pr_err("names[%d] = %p = %s\n", i++, n->name, - n->name->name ?: "(null)"); - } - dump_stack(); - return; - } -#endif -#if AUDIT_DEBUG - context->put_count = 0; - context->ino_count = 0; -#endif - list_for_each_entry_safe(n, next, &context->names_list, list) { list_del(&n->list); - if (n->name && n->name_put) - final_putname(n->name); + if (n->name) + putname(n->name); if (n->should_free) kfree(n); } @@ -1711,9 +1688,6 @@ static struct audit_names *audit_alloc_name(struct audit_context *context, list_add_tail(&aname->list, &context->names_list); context->name_count++; -#if AUDIT_DEBUG - context->ino_count++; -#endif return aname; } @@ -1734,8 +1708,10 @@ __audit_reusename(const __user char *uptr) list_for_each_entry(n, &context->names_list, list) { if (!n->name) continue; - if (n->name->uptr == uptr) + if (n->name->uptr == uptr) { + n->name->refcnt++; return n->name; + } } return NULL; } @@ -1752,19 +1728,8 @@ void __audit_getname(struct filename *name) struct audit_context *context = current->audit_context; struct audit_names *n; - if (!context->in_syscall) { -#if AUDIT_DEBUG == 2 - pr_err("%s:%d(:%d): ignoring getname(%p)\n", - __FILE__, __LINE__, context->serial, name); - dump_stack(); -#endif + if (!context->in_syscall) return; - } - -#if AUDIT_DEBUG - /* The filename _must_ have a populated ->name */ - BUG_ON(!name->name); -#endif n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); if (!n) @@ -1772,56 +1737,13 @@ void __audit_getname(struct filename *name) n->name = name; n->name_len = AUDIT_NAME_FULL; - n->name_put = true; name->aname = n; + name->refcnt++; if (!context->pwd.dentry) get_fs_pwd(current->fs, &context->pwd); } -/* audit_putname - intercept a putname request - * @name: name to intercept and delay for putname - * - * If we have stored the name from getname in the audit context, - * then we delay the putname until syscall exit. - * Called from include/linux/fs.h:putname(). - */ -void audit_putname(struct filename *name) -{ - struct audit_context *context = current->audit_context; - - BUG_ON(!context); - if (!name->aname || !context->in_syscall) { -#if AUDIT_DEBUG == 2 - pr_err("%s:%d(:%d): final_putname(%p)\n", - __FILE__, __LINE__, context->serial, name); - if (context->name_count) { - struct audit_names *n; - int i = 0; - - list_for_each_entry(n, &context->names_list, list) - pr_err("name[%d] = %p = %s\n", i++, n->name, - n->name->name ?: "(null)"); - } -#endif - final_putname(name); - } -#if AUDIT_DEBUG - else { - ++context->put_count; - if (context->put_count > context->name_count) { - pr_err("%s:%d(:%d): major=%d in_syscall=%d putname(%p)" - " name_count=%d put_count=%d\n", - __FILE__, __LINE__, - context->serial, context->major, - context->in_syscall, name->name, - context->name_count, context->put_count); - dump_stack(); - } - } -#endif -} - /** * __audit_inode - store the inode and device from a lookup * @name: name being audited @@ -1842,10 +1764,6 @@ void __audit_inode(struct filename *name, const struct dentry *dentry, if (!name) goto out_alloc; -#if AUDIT_DEBUG - /* The struct filename _must_ have a populated ->name */ - BUG_ON(!name->name); -#endif /* * If we have a pointer to an audit_names entry already, then we can * just use it directly if the type is correct. @@ -1863,7 +1781,17 @@ void __audit_inode(struct filename *name, const struct dentry *dentry, } list_for_each_entry_reverse(n, &context->names_list, list) { - if (!n->name || strcmp(n->name->name, name->name)) + if (n->ino) { + /* valid inode number, use that for the comparison */ + if (n->ino != inode->i_ino || + n->dev != inode->i_sb->s_dev) + continue; + } else if (n->name) { + /* inode number has not been set, check the name */ + if (strcmp(n->name->name, name->name)) + continue; + } else + /* no inode and no name (?!) ... this is odd ... */ continue; /* match the correct record type */ @@ -1882,44 +1810,11 @@ out_alloc: n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN); if (!n) return; - /* unfortunately, while we may have a path name to record with the - * inode, we can't always rely on the string lasting until the end of - * the syscall so we need to create our own copy, it may fail due to - * memory allocation issues, but we do our best */ if (name) { - /* we can't use getname_kernel() due to size limits */ - size_t len = strlen(name->name) + 1; - struct filename *new = __getname(); - - if (unlikely(!new)) - goto out; - - if (len <= (PATH_MAX - sizeof(*new))) { - new->name = (char *)(new) + sizeof(*new); - new->separate = false; - } else if (len <= PATH_MAX) { - /* this looks odd, but is due to final_putname() */ - struct filename *new2; - - new2 = kmalloc(sizeof(*new2), GFP_KERNEL); - if (unlikely(!new2)) { - __putname(new); - goto out; - } - new2->name = (char *)new; - new2->separate = true; - new = new2; - } else { - /* we should never get here, but let's be safe */ - __putname(new); - goto out; - } - strlcpy((char *)new->name, name->name, len); - new->uptr = NULL; - new->aname = n; - n->name = new; - n->name_put = true; + n->name = name; + name->refcnt++; } + out: if (parent) { n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL; @@ -1970,11 +1865,16 @@ void __audit_inode_child(const struct inode *parent, /* look for a parent entry first */ list_for_each_entry(n, &context->names_list, list) { - if (!n->name || n->type != AUDIT_TYPE_PARENT) + if (!n->name || + (n->type != AUDIT_TYPE_PARENT && + n->type != AUDIT_TYPE_UNKNOWN)) continue; - if (n->ino == parent->i_ino && - !audit_compare_dname_path(dname, n->name->name, n->name_len)) { + if (n->ino == parent->i_ino && n->dev == parent->i_sb->s_dev && + !audit_compare_dname_path(dname, + n->name->name, n->name_len)) { + if (n->type == AUDIT_TYPE_UNKNOWN) + n->type = AUDIT_TYPE_PARENT; found_parent = n; break; } @@ -1983,11 +1883,8 @@ void __audit_inode_child(const struct inode *parent, /* is there a matching child entry? */ list_for_each_entry(n, &context->names_list, list) { /* can only match entries that have a name */ - if (!n->name || n->type != type) - continue; - - /* if we found a parent, make sure this one is a child of it */ - if (found_parent && (n->name != found_parent->name)) + if (!n->name || + (n->type != type && n->type != AUDIT_TYPE_UNKNOWN)) continue; if (!strcmp(dname, n->name->name) || @@ -1995,6 +1892,8 @@ void __audit_inode_child(const struct inode *parent, found_parent ? found_parent->name_len : AUDIT_NAME_FULL)) { + if (n->type == AUDIT_TYPE_UNKNOWN) + n->type = type; found_child = n; break; } @@ -2019,10 +1918,10 @@ void __audit_inode_child(const struct inode *parent, if (found_parent) { found_child->name = found_parent->name; found_child->name_len = AUDIT_NAME_FULL; - /* don't call __putname() */ - found_child->name_put = false; + found_child->name->refcnt++; } } + if (inode) audit_copy_inode(found_child, dentry, inode); else |