From 0b52075ee62301dd150c9f2c3ddd0035ed894cde Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 23 Dec 2018 16:02:47 -0500 Subject: introduce cloning of fs_context new primitive: vfs_dup_fs_context(). Comes with fs_context method (->dup()) for copying the filesystem-specific parts of fs_context, along with LSM one (->fs_context_dup()) for doing the same to LSM parts. [needs better commit message, and change of Author:, anyway] Signed-off-by: Al Viro --- security/security.c | 5 +++++ security/selinux/hooks.c | 39 ++++++++++++++++++++++++++++++++++++ security/smack/smack_lsm.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 93 insertions(+) (limited to 'security') diff --git a/security/security.c b/security/security.c index e5519488327d..5759339319dc 100644 --- a/security/security.c +++ b/security/security.c @@ -374,6 +374,11 @@ void security_bprm_committed_creds(struct linux_binprm *bprm) call_void_hook(bprm_committed_creds, bprm); } +int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) +{ + return call_int_hook(fs_context_dup, 0, fc, src_fc); +} + int security_fs_context_parse_param(struct fs_context *fc, struct fs_parameter *param) { return call_int_hook(fs_context_parse_param, -ENOPARAM, fc, param); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index f99381e97d73..4ba83de5fa80 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2764,6 +2764,44 @@ static int selinux_umount(struct vfsmount *mnt, int flags) FILESYSTEM__UNMOUNT, NULL); } +static int selinux_fs_context_dup(struct fs_context *fc, + struct fs_context *src_fc) +{ + const struct selinux_mnt_opts *src = src_fc->security; + struct selinux_mnt_opts *opts; + + if (!src) + return 0; + + fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL); + if (!fc->security) + return -ENOMEM; + + opts = fc->security; + + if (src->fscontext) { + opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL); + if (!opts->fscontext) + return -ENOMEM; + } + if (src->context) { + opts->context = kstrdup(src->context, GFP_KERNEL); + if (!opts->context) + return -ENOMEM; + } + if (src->rootcontext) { + opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL); + if (!opts->rootcontext) + return -ENOMEM; + } + if (src->defcontext) { + opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL); + if (!opts->defcontext) + return -ENOMEM; + } + return 0; +} + static const struct fs_parameter_spec selinux_param_specs[] = { fsparam_string(CONTEXT_STR, Opt_context), fsparam_string(DEFCONTEXT_STR, Opt_defcontext), @@ -6745,6 +6783,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), + 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_alloc_security, selinux_sb_alloc_security), diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 5f93c4f84384..03176f600a87 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -647,6 +647,54 @@ out_opt_err: return -EINVAL; } +/** + * 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. + * + * Returns 0 on success or -ENOMEM on error. + */ +static int smack_fs_context_dup(struct fs_context *fc, + struct fs_context *src_fc) +{ + struct smack_mnt_opts *dst, *src = src_fc->security; + + if (!src) + return 0; + + fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL); + if (!fc->security) + return -ENOMEM; + dst = fc->security; + + if (src->fsdefault) { + dst->fsdefault = kstrdup(src->fsdefault, GFP_KERNEL); + if (!dst->fsdefault) + return -ENOMEM; + } + if (src->fsfloor) { + dst->fsfloor = kstrdup(src->fsfloor, GFP_KERNEL); + if (!dst->fsfloor) + return -ENOMEM; + } + if (src->fshat) { + dst->fshat = kstrdup(src->fshat, GFP_KERNEL); + if (!dst->fshat) + return -ENOMEM; + } + if (src->fsroot) { + dst->fsroot = kstrdup(src->fsroot, GFP_KERNEL); + if (!dst->fsroot) + return -ENOMEM; + } + if (src->fstransmute) { + dst->fstransmute = kstrdup(src->fstransmute, GFP_KERNEL); + if (!dst->fstransmute) + return -ENOMEM; + } + return 0; +} + static const struct fs_parameter_spec smack_param_specs[] = { fsparam_string("fsdefault", Opt_fsdefault), fsparam_string("fsfloor", Opt_fsfloor), @@ -4626,6 +4674,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme), LSM_HOOK_INIT(syslog, smack_syslog), + LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup), LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param), LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security), -- cgit v1.2.3-59-g8ed1b