diff options
| -rw-r--r-- | fs/fs_context.c | 23 | ||||
| -rw-r--r-- | include/linux/lsm_hook_defs.h | 1 | ||||
| -rw-r--r-- | include/linux/security.h | 6 | ||||
| -rw-r--r-- | security/security.c | 14 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 22 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 51 |
6 files changed, 116 insertions, 1 deletions
diff --git a/fs/fs_context.c b/fs/fs_context.c index 851214d1d013..375023e40161 100644 --- a/fs/fs_context.c +++ b/fs/fs_context.c @@ -315,10 +315,31 @@ struct fs_context *fs_context_for_reconfigure(struct dentry *dentry, } EXPORT_SYMBOL(fs_context_for_reconfigure); +/** + * fs_context_for_submount: allocate a new fs_context for a submount + * @type: file_system_type of the new context + * @reference: reference dentry from which to copy relevant info + * + * Allocate a new fs_context suitable for a submount. This also ensures that + * the fc->security object is inherited from @reference (if needed). + */ struct fs_context *fs_context_for_submount(struct file_system_type *type, struct dentry *reference) { - return alloc_fs_context(type, reference, 0, 0, FS_CONTEXT_FOR_SUBMOUNT); + struct fs_context *fc; + int ret; + + fc = alloc_fs_context(type, reference, 0, 0, FS_CONTEXT_FOR_SUBMOUNT); + if (IS_ERR(fc)) + return fc; + + ret = security_fs_context_submount(fc, reference->d_sb); + if (ret) { + put_fs_context(fc); + return ERR_PTR(ret); + } + + return fc; } EXPORT_SYMBOL(fs_context_for_submount); diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 7308a1a7599b..af796986baee 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -54,6 +54,7 @@ LSM_HOOK(int, 0, bprm_creds_from_file, struct linux_binprm *bprm, struct file *f LSM_HOOK(int, 0, bprm_check_security, struct linux_binprm *bprm) LSM_HOOK(void, LSM_RET_VOID, bprm_committing_creds, struct linux_binprm *bprm) LSM_HOOK(void, LSM_RET_VOID, bprm_committed_creds, struct linux_binprm *bprm) +LSM_HOOK(int, 0, fs_context_submount, struct fs_context *fc, struct super_block *reference) LSM_HOOK(int, 0, fs_context_dup, struct fs_context *fc, struct fs_context *src_sc) LSM_HOOK(int, -ENOPARAM, fs_context_parse_param, struct fs_context *fc, diff --git a/include/linux/security.h b/include/linux/security.h index 32828502f09e..bac98ea18f78 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -293,6 +293,7 @@ int security_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file); int security_bprm_check(struct linux_binprm *bprm); void security_bprm_committing_creds(struct linux_binprm *bprm); void security_bprm_committed_creds(struct linux_binprm *bprm); +int security_fs_context_submount(struct fs_context *fc, struct super_block *reference); int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc); int security_fs_context_parse_param(struct fs_context *fc, struct fs_parameter *param); int security_sb_alloc(struct super_block *sb); @@ -629,6 +630,11 @@ static inline void security_bprm_committed_creds(struct linux_binprm *bprm) { } +static inline int security_fs_context_submount(struct fs_context *fc, + struct super_block *reference) +{ + return 0; +} static inline int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) { diff --git a/security/security.c b/security/security.c index b720424ca37d..549104a447e3 100644 --- a/security/security.c +++ b/security/security.c @@ -1139,6 +1139,20 @@ void security_bprm_committed_creds(struct linux_binprm *bprm) } /** + * security_fs_context_submount() - Initialise fc->security + * @fc: new filesystem context + * @reference: dentry reference for submount/remount + * + * Fill out the ->security field for a new fs_context. + * + * Return: Returns 0 on success or negative error code on failure. + */ +int security_fs_context_submount(struct fs_context *fc, struct super_block *reference) +{ + return call_int_hook(fs_context_submount, 0, fc, reference); +} + +/** * security_fs_context_dup() - Duplicate a fs_context LSM blob * @fc: destination filesystem context * @src_fc: source filesystem context diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index d06e350fedee..afd663744041 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2745,6 +2745,27 @@ static int selinux_umount(struct vfsmount *mnt, int flags) FILESYSTEM__UNMOUNT, NULL); } +static int selinux_fs_context_submount(struct fs_context *fc, + struct super_block *reference) +{ + const struct superblock_security_struct *sbsec; + struct selinux_mnt_opts *opts; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return -ENOMEM; + + sbsec = selinux_superblock(reference); + if (sbsec->flags & FSCONTEXT_MNT) + opts->fscontext_sid = sbsec->sid; + if (sbsec->flags & CONTEXT_MNT) + opts->context_sid = sbsec->mntpoint_sid; + if (sbsec->flags & DEFCONTEXT_MNT) + opts->defcontext_sid = sbsec->def_sid; + fc->security = opts; + return 0; +} + static int selinux_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) { @@ -7182,6 +7203,7 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = { /* * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE */ + LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount), LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup), LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param), LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts), diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 6e270cf3fd30..a8201cf22f20 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -615,6 +615,56 @@ out_opt_err: } /** + * smack_fs_context_submount - Initialise security data for a filesystem context + * @fc: The filesystem context. + * @reference: reference superblock + * + * Returns 0 on success or -ENOMEM on error. + */ +static int smack_fs_context_submount(struct fs_context *fc, + struct super_block *reference) +{ + struct superblock_smack *sbsp; + struct smack_mnt_opts *ctx; + struct inode_smack *isp; + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + fc->security = ctx; + + sbsp = smack_superblock(reference); + isp = smack_inode(reference->s_root->d_inode); + + if (sbsp->smk_default) { + ctx->fsdefault = kstrdup(sbsp->smk_default->smk_known, GFP_KERNEL); + if (!ctx->fsdefault) + return -ENOMEM; + } + + if (sbsp->smk_floor) { + ctx->fsfloor = kstrdup(sbsp->smk_floor->smk_known, GFP_KERNEL); + if (!ctx->fsfloor) + return -ENOMEM; + } + + if (sbsp->smk_hat) { + ctx->fshat = kstrdup(sbsp->smk_hat->smk_known, GFP_KERNEL); + if (!ctx->fshat) + return -ENOMEM; + } + + if (isp->smk_flags & SMK_INODE_TRANSMUTE) { + if (sbsp->smk_root) { + ctx->fstransmute = kstrdup(sbsp->smk_root->smk_known, GFP_KERNEL); + if (!ctx->fstransmute) + return -ENOMEM; + } + } + return 0; +} + +/** * smack_fs_context_dup - Duplicate the security data on fs_context duplication * @fc: The new filesystem context. * @src_fc: The source filesystem context being duplicated. @@ -4876,6 +4926,7 @@ static struct security_hook_list smack_hooks[] __ro_after_init = { LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme), LSM_HOOK_INIT(syslog, smack_syslog), + LSM_HOOK_INIT(fs_context_submount, smack_fs_context_submount), LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup), LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param), |