diff options
| -rw-r--r-- | fs/namespace.c | 4 | ||||
| -rw-r--r-- | include/linux/security.h | 13 | ||||
| -rw-r--r-- | security/capability.c | 6 | ||||
| -rw-r--r-- | security/security.c | 5 |
4 files changed, 28 insertions, 0 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 3ddfd9046c44..1b3f2ac59c5e 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1800,6 +1800,10 @@ static int do_remount(struct path *path, int flags, int mnt_flags, if (path->dentry != path->mnt->mnt_root) return -EINVAL; + err = security_sb_remount(sb, data); + if (err) + return err; + down_write(&sb->s_umount); if (flags & MS_BIND) err = change_mount_flags(path->mnt, flags); diff --git a/include/linux/security.h b/include/linux/security.h index 14167f2eb35a..d11ac43ecc49 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -268,6 +268,12 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @orig the original mount data copied from userspace. * @copy copied data which will be passed to the security module. * Returns 0 if the copy was successful. + * @sb_remount: + * Extracts security system specifc mount options and verifys no changes + * are being made to those options. + * @sb superblock being remounted + * @data contains the filesystem-specific data. + * Return 0 if permission is granted. * @sb_umount: * Check permission before the @mnt file system is unmounted. * @mnt contains the mounted file system. @@ -1394,6 +1400,7 @@ struct security_operations { int (*sb_alloc_security) (struct super_block *sb); void (*sb_free_security) (struct super_block *sb); int (*sb_copy_data) (char *orig, char *copy); + int (*sb_remount) (struct super_block *sb, void *data); int (*sb_kern_mount) (struct super_block *sb, int flags, void *data); int (*sb_show_options) (struct seq_file *m, struct super_block *sb); int (*sb_statfs) (struct dentry *dentry); @@ -1676,6 +1683,7 @@ int security_bprm_secureexec(struct linux_binprm *bprm); int security_sb_alloc(struct super_block *sb); void security_sb_free(struct super_block *sb); int security_sb_copy_data(char *orig, char *copy); +int security_sb_remount(struct super_block *sb, void *data); int security_sb_kern_mount(struct super_block *sb, int flags, void *data); int security_sb_show_options(struct seq_file *m, struct super_block *sb); int security_sb_statfs(struct dentry *dentry); @@ -1955,6 +1963,11 @@ static inline int security_sb_copy_data(char *orig, char *copy) return 0; } +static inline int security_sb_remount(struct super_block *sb, void *data) +{ + return 0; +} + static inline int security_sb_kern_mount(struct super_block *sb, int flags, void *data) { return 0; diff --git a/security/capability.c b/security/capability.c index 85b67c8632df..ab3d807accc3 100644 --- a/security/capability.c +++ b/security/capability.c @@ -54,6 +54,11 @@ static int cap_sb_copy_data(char *orig, char *copy) return 0; } +static int cap_sb_remount(struct super_block *sb, void *data) +{ + return 0; +} + static int cap_sb_kern_mount(struct super_block *sb, int flags, void *data) { return 0; @@ -887,6 +892,7 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, sb_alloc_security); set_to_cap_if_null(ops, sb_free_security); set_to_cap_if_null(ops, sb_copy_data); + set_to_cap_if_null(ops, sb_remount); set_to_cap_if_null(ops, sb_kern_mount); set_to_cap_if_null(ops, sb_show_options); set_to_cap_if_null(ops, sb_statfs); diff --git a/security/security.c b/security/security.c index 8f28685ee0d9..b1d6134548bc 100644 --- a/security/security.c +++ b/security/security.c @@ -267,6 +267,11 @@ int security_sb_copy_data(char *orig, char *copy) } EXPORT_SYMBOL(security_sb_copy_data); +int security_sb_remount(struct super_block *sb, void *data) +{ + return security_ops->sb_remount(sb, data); +} + int security_sb_kern_mount(struct super_block *sb, int flags, void *data) { return security_ops->sb_kern_mount(sb, flags, data); |