diff options
Diffstat (limited to 'security/selinux')
-rw-r--r-- | security/selinux/hooks.c | 176 | ||||
-rw-r--r-- | security/selinux/include/security.h | 5 |
2 files changed, 100 insertions, 81 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 75c2e99bfb8..41a049f50f5 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -443,8 +443,7 @@ out: * mount options, or whatever. */ static int selinux_get_mnt_opts(const struct super_block *sb, - char ***mount_options, int **mnt_opts_flags, - int *num_opts) + struct security_mnt_opts *opts) { int rc = 0, i; struct superblock_security_struct *sbsec = sb->s_security; @@ -452,9 +451,7 @@ static int selinux_get_mnt_opts(const struct super_block *sb, u32 len; char tmp; - *num_opts = 0; - *mount_options = NULL; - *mnt_opts_flags = NULL; + security_init_mnt_opts(opts); if (!sbsec->initialized) return -EINVAL; @@ -470,18 +467,18 @@ static int selinux_get_mnt_opts(const struct super_block *sb, /* count the number of mount options for this sb */ for (i = 0; i < 8; i++) { if (tmp & 0x01) - (*num_opts)++; + opts->num_mnt_opts++; tmp >>= 1; } - *mount_options = kcalloc(*num_opts, sizeof(char *), GFP_ATOMIC); - if (!*mount_options) { + opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); + if (!opts->mnt_opts) { rc = -ENOMEM; goto out_free; } - *mnt_opts_flags = kcalloc(*num_opts, sizeof(int), GFP_ATOMIC); - if (!*mnt_opts_flags) { + opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); + if (!opts->mnt_opts_flags) { rc = -ENOMEM; goto out_free; } @@ -491,22 +488,22 @@ static int selinux_get_mnt_opts(const struct super_block *sb, rc = security_sid_to_context(sbsec->sid, &context, &len); if (rc) goto out_free; - (*mount_options)[i] = context; - (*mnt_opts_flags)[i++] = FSCONTEXT_MNT; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; } if (sbsec->flags & CONTEXT_MNT) { rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); if (rc) goto out_free; - (*mount_options)[i] = context; - (*mnt_opts_flags)[i++] = CONTEXT_MNT; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = CONTEXT_MNT; } if (sbsec->flags & DEFCONTEXT_MNT) { rc = security_sid_to_context(sbsec->def_sid, &context, &len); if (rc) goto out_free; - (*mount_options)[i] = context; - (*mnt_opts_flags)[i++] = DEFCONTEXT_MNT; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; } if (sbsec->flags & ROOTCONTEXT_MNT) { struct inode *root = sbsec->sb->s_root->d_inode; @@ -515,24 +512,16 @@ static int selinux_get_mnt_opts(const struct super_block *sb, rc = security_sid_to_context(isec->sid, &context, &len); if (rc) goto out_free; - (*mount_options)[i] = context; - (*mnt_opts_flags)[i++] = ROOTCONTEXT_MNT; + opts->mnt_opts[i] = context; + opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; } - BUG_ON(i != *num_opts); + BUG_ON(i != opts->num_mnt_opts); return 0; out_free: - /* don't leak context string if security_sid_to_context had an error */ - if (*mount_options && i) - for (; i > 0; i--) - kfree((*mount_options)[i-1]); - kfree(*mount_options); - *mount_options = NULL; - kfree(*mnt_opts_flags); - *mnt_opts_flags = NULL; - *num_opts = 0; + security_free_mnt_opts(opts); return rc; } @@ -553,12 +542,13 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag, return 1; return 0; } + /* * Allow filesystems with binary mount data to explicitly set mount point * labeling information. */ -static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options, - int *flags, int num_opts) +static int selinux_set_mnt_opts(struct super_block *sb, + struct security_mnt_opts *opts) { int rc = 0, i; struct task_security_struct *tsec = current->security; @@ -568,6 +558,9 @@ static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options, struct inode_security_struct *root_isec = inode->i_security; u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; u32 defcontext_sid = 0; + char **mount_options = opts->mnt_opts; + int *flags = opts->mnt_opts_flags; + int num_opts = opts->num_mnt_opts; mutex_lock(&sbsec->lock); @@ -589,6 +582,21 @@ static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options, } /* + * Binary mount data FS will come through this function twice. Once + * from an explicit call and once from the generic calls from the vfs. + * Since the generic VFS calls will not contain any security mount data + * we need to skip the double mount verification. + * + * This does open a hole in which we will not notice if the first + * mount using this sb set explict options and a second mount using + * this sb does not set any security options. (The first options + * will be used for both mounts) + */ + if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) + && (num_opts == 0)) + goto out; + + /* * parse the mount options, check if they are valid sids. * also check if someone is trying to mount the same sb more * than once with different security options. @@ -792,43 +800,15 @@ static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, mutex_unlock(&newsbsec->lock); } -/* - * string mount options parsing and call set the sbsec - */ -static int superblock_doinit(struct super_block *sb, void *data) +static int selinux_parse_opts_str(char *options, + struct security_mnt_opts *opts) { + char *p; char *context = NULL, *defcontext = NULL; char *fscontext = NULL, *rootcontext = NULL; - int rc = 0; - char *p, *options = data; - /* selinux only know about a fixed number of mount options */ - char *mnt_opts[NUM_SEL_MNT_OPTS]; - int mnt_opts_flags[NUM_SEL_MNT_OPTS], num_mnt_opts = 0; - - if (!data) - goto out; + int rc, num_mnt_opts = 0; - /* with the nfs patch this will become a goto out; */ - if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { - const char *name = sb->s_type->name; - /* NFS we understand. */ - if (!strcmp(name, "nfs")) { - struct nfs_mount_data *d = data; - - if (d->version != NFS_MOUNT_VERSION) - goto out; - - if (d->context[0]) { - context = kstrdup(d->context, GFP_KERNEL); - if (!context) { - rc = -ENOMEM; - goto out; - } - } - goto build_flags; - } else - goto out; - } + opts->num_mnt_opts = 0; /* Standard string-based options. */ while ((p = strsep(&options, "|")) != NULL) { @@ -901,26 +881,37 @@ static int superblock_doinit(struct super_block *sb, void *data) } } -build_flags: + rc = -ENOMEM; + opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); + if (!opts->mnt_opts) + goto out_err; + + opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); + if (!opts->mnt_opts_flags) { + kfree(opts->mnt_opts); + goto out_err; + } + if (fscontext) { - mnt_opts[num_mnt_opts] = fscontext; - mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; + opts->mnt_opts[num_mnt_opts] = fscontext; + opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; } if (context) { - mnt_opts[num_mnt_opts] = context; - mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; + opts->mnt_opts[num_mnt_opts] = context; + opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; } if (rootcontext) { - mnt_opts[num_mnt_opts] = rootcontext; - mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; + opts->mnt_opts[num_mnt_opts] = rootcontext; + opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; } if (defcontext) { - mnt_opts[num_mnt_opts] = defcontext; - mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; + opts->mnt_opts[num_mnt_opts] = defcontext; + opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; } -out: - rc = selinux_set_mnt_opts(sb, mnt_opts, mnt_opts_flags, num_mnt_opts); + opts->num_mnt_opts = num_mnt_opts; + return 0; + out_err: kfree(context); kfree(defcontext); @@ -928,6 +919,33 @@ out_err: kfree(rootcontext); return rc; } +/* + * string mount options parsing and call set the sbsec + */ +static int superblock_doinit(struct super_block *sb, void *data) +{ + int rc = 0; + char *options = data; + struct security_mnt_opts opts; + + security_init_mnt_opts(&opts); + + if (!data) + goto out; + + BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); + + rc = selinux_parse_opts_str(options, &opts); + if (rc) + goto out_err; + +out: + rc = selinux_set_mnt_opts(sb, &opts); + +out_err: + security_free_mnt_opts(&opts); + return rc; +} static inline u16 inode_mode_to_security_class(umode_t mode) { @@ -2253,7 +2271,7 @@ static inline void take_selinux_option(char **to, char *from, int *first, } } -static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) +static int selinux_sb_copy_data(char *orig, char *copy) { int fnosec, fsec, rc = 0; char *in_save, *in_curr, *in_end; @@ -2263,12 +2281,6 @@ static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void in_curr = orig; sec_curr = copy; - /* Binary mount data: just copy */ - if (type->fs_flags & FS_BINARY_MOUNTDATA) { - copy_page(sec_curr, in_curr); - goto out; - } - nosec = (char *)get_zeroed_page(GFP_KERNEL); if (!nosec) { rc = -ENOMEM; @@ -5251,6 +5263,8 @@ static struct security_operations selinux_ops = { .sb_get_mnt_opts = selinux_get_mnt_opts, .sb_set_mnt_opts = selinux_set_mnt_opts, .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, + .sb_parse_opts_str = selinux_parse_opts_str, + .inode_alloc_security = selinux_inode_alloc_security, .inode_free_security = selinux_inode_free_security, diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 837ce420d2f..f7d2f03781f 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -35,6 +35,11 @@ #define POLICYDB_VERSION_MAX POLICYDB_VERSION_POLCAP #endif +#define CONTEXT_MNT 0x01 +#define FSCONTEXT_MNT 0x02 +#define ROOTCONTEXT_MNT 0x04 +#define DEFCONTEXT_MNT 0x08 + struct netlbl_lsm_secattr; extern int selinux_enabled; |