From 757cbe597fe8490c7c0a9650ebe5d60195f151d4 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 14 Dec 2018 23:42:21 -0500 Subject: [PATCH] LSM: new method: ->sb_add_mnt_opt() Adding options to growing mnt_opts. NFS kludge with passing context= down into non-text-options mount switched to it, and with that the last use of ->sb_parse_opts_str() is gone. Reviewed-by: David Howells Signed-off-by: Al Viro --- fs/nfs/super.c | 9 ++------- include/linux/lsm_hooks.h | 5 +++-- include/linux/security.h | 6 ++++-- security/security.c | 8 +++++--- security/selinux/hooks.c | 45 +++++++++++++++++++-------------------------- security/smack/smack_lsm.c | 1 - 6 files changed, 33 insertions(+), 41 deletions(-) diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 1943de8..073eec2 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -2070,14 +2070,9 @@ static int nfs23_validate_mount_data(void *options, if (data->context[0]){ #ifdef CONFIG_SECURITY_SELINUX int rc; - char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL); - if (!opts_str) - return -ENOMEM; - strcpy(opts_str, "context="); data->context[NFS_MAX_CONTEXT_LEN] = '\0'; - strcat(opts_str, &data->context[0]); - rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts); - kfree(opts_str); + rc = security_add_mnt_opt("context", data->context, + strlen(data->context), &args->lsm_opts); if (rc) return rc; #else diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index a9c541f..9a0bdf9 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1479,7 +1479,8 @@ union security_list_options { struct super_block *newsb, unsigned long kern_flags, unsigned long *set_kern_flags); - int (*sb_parse_opts_str)(char *options, void **mnt_opts); + int (*sb_add_mnt_opt)(const char *option, const char *val, int len, + void **mnt_opts); int (*dentry_init_security)(struct dentry *dentry, int mode, const struct qstr *name, void **ctx, u32 *ctxlen); @@ -1812,7 +1813,7 @@ struct security_hook_heads { struct hlist_head sb_pivotroot; struct hlist_head sb_set_mnt_opts; struct hlist_head sb_clone_mnt_opts; - struct hlist_head sb_parse_opts_str; + struct hlist_head sb_add_mnt_opt; struct hlist_head dentry_init_security; struct hlist_head dentry_create_files_as; #ifdef CONFIG_SECURITY_PATH diff --git a/include/linux/security.h b/include/linux/security.h index ae8d5ac..dbfb5a6 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -240,7 +240,8 @@ int security_sb_clone_mnt_opts(const struct super_block *oldsb, struct super_block *newsb, unsigned long kern_flags, unsigned long *set_kern_flags); -int security_sb_parse_opts_str(char *options, void **mnt_opts); +int security_add_mnt_opt(const char *option, const char *val, + int len, void **mnt_opts); int security_dentry_init_security(struct dentry *dentry, int mode, const struct qstr *name, void **ctx, u32 *ctxlen); @@ -586,7 +587,8 @@ static inline int security_sb_clone_mnt_opts(const struct super_block *oldsb, return 0; } -static inline int security_sb_parse_opts_str(char *options, void **mnt_opts) +static inline int security_add_mnt_opt(const char *option, const char *val, + int len, void **mnt_opts) { return 0; } diff --git a/security/security.c b/security/security.c index b7a5a00..c251278 100644 --- a/security/security.c +++ b/security/security.c @@ -458,11 +458,13 @@ int security_sb_clone_mnt_opts(const struct super_block *oldsb, } EXPORT_SYMBOL(security_sb_clone_mnt_opts); -int security_sb_parse_opts_str(char *options, void **mnt_opts) +int security_add_mnt_opt(const char *option, const char *val, int len, + void **mnt_opts) { - return call_int_hook(sb_parse_opts_str, 0, options, mnt_opts); + return call_int_hook(sb_add_mnt_opt, -EINVAL, + option, val, len, mnt_opts); } -EXPORT_SYMBOL(security_sb_parse_opts_str); +EXPORT_SYMBOL(security_add_mnt_opt); int security_inode_alloc(struct inode *inode) { diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 5336d66..5bc2303 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1049,40 +1049,33 @@ Einval: return -EINVAL; } -static int selinux_parse_opts_str(char *options, - void **mnt_opts) +static int selinux_add_mnt_opt(const char *option, const char *val, int len, + void **mnt_opts) { - char *p = options, *next; - int rc; - - /* Standard string-based options. */ - for (p = options; *p; p = next) { - int token, len; - char *arg = NULL; + int token = Opt_error; + int rc, i; - next = strchr(p, '|'); - if (next) { - len = next++ - p; - } else { - len = strlen(p); - next = p + len; + for (i = 0; i < ARRAY_SIZE(tokens); i++) { + if (strcmp(option, tokens[i].name) == 0) { + token = tokens[i].opt; + break; } + } - if (!len) - continue; + if (token == Opt_error) + return -EINVAL; - token = match_opt_prefix(p, len, &arg); - if (arg) - arg = kmemdup_nul(arg, p + len - arg, GFP_KERNEL); - rc = selinux_add_opt(token, arg, mnt_opts); - if (rc) { - kfree(arg); + if (token != Opt_seclabel) + val = kmemdup_nul(val, len, GFP_KERNEL); + rc = selinux_add_opt(token, val, mnt_opts); + if (unlikely(rc)) { + kfree(val); + if (*mnt_opts) { selinux_free_mnt_opts(*mnt_opts); *mnt_opts = NULL; - return rc; } } - return 0; + return rc; } static int show_sid(struct seq_file *m, u32 sid) @@ -6726,7 +6719,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(sb_umount, selinux_umount), LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), - LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str), + LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt), LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 99aec9f..b607b11 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -4629,7 +4629,6 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts), LSM_HOOK_INIT(sb_statfs, smack_sb_statfs), LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts), - LSM_HOOK_INIT(sb_parse_opts_str, smack_parse_opts_str), LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds), -- 2.7.4