From fb4021b6fb5818df1228a35b7e2645038d01bb9f Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Mon, 12 Nov 2018 12:43:01 -0800 Subject: Smack: Abstract use of inode security blob Don't use the inode->i_security pointer directly. Provide a helper function that provides the security blob pointer. Signed-off-by: Casey Schaufler Reviewed-by: Kees Cook Signed-off-by: Kees Cook --- security/smack/smack.h | 9 +++++++-- security/smack/smack_lsm.c | 32 ++++++++++++++++---------------- 2 files changed, 23 insertions(+), 18 deletions(-) (limited to 'security') diff --git a/security/smack/smack.h b/security/smack/smack.h index 2007d38d0e46..436231dfae33 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -368,12 +368,17 @@ static inline struct smack_known **smack_file(const struct file *file) smack_blob_sizes.lbs_file); } +static inline struct inode_smack *smack_inode(const struct inode *inode) +{ + return inode->i_security; +} + /* * Is the directory transmuting? */ static inline int smk_inode_transmutable(const struct inode *isp) { - struct inode_smack *sip = isp->i_security; + struct inode_smack *sip = smack_inode(isp); return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0; } @@ -382,7 +387,7 @@ static inline int smk_inode_transmutable(const struct inode *isp) */ static inline struct smack_known *smk_of_inode(const struct inode *isp) { - struct inode_smack *sip = isp->i_security; + struct inode_smack *sip = smack_inode(isp); return sip->smk_inode; } diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 7c76668ea3a6..ddffda39d107 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -183,7 +183,7 @@ static int smk_bu_task(struct task_struct *otp, int mode, int rc) static int smk_bu_inode(struct inode *inode, int mode, int rc) { struct task_smack *tsp = smack_cred(current_cred()); - struct inode_smack *isp = inode->i_security; + struct inode_smack *isp = smack_inode(inode); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (isp->smk_flags & SMK_INODE_IMPURE) @@ -215,7 +215,7 @@ static int smk_bu_file(struct file *file, int mode, int rc) struct task_smack *tsp = smack_cred(current_cred()); struct smack_known *sskp = tsp->smk_task; struct inode *inode = file_inode(file); - struct inode_smack *isp = inode->i_security; + struct inode_smack *isp = smack_inode(inode); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (isp->smk_flags & SMK_INODE_IMPURE) @@ -245,7 +245,7 @@ static int smk_bu_credfile(const struct cred *cred, struct file *file, struct task_smack *tsp = smack_cred(cred); struct smack_known *sskp = tsp->smk_task; struct inode *inode = file_inode(file); - struct inode_smack *isp = inode->i_security; + struct inode_smack *isp = smack_inode(inode); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (isp->smk_flags & SMK_INODE_IMPURE) @@ -773,7 +773,7 @@ static int smack_set_mnt_opts(struct super_block *sb, /* * Initialize the root inode. */ - isp = inode->i_security; + isp = smack_inode(inode); if (isp == NULL) { isp = new_inode_smack(sp->smk_root); if (isp == NULL) @@ -830,7 +830,7 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm) if (bprm->called_set_creds) return 0; - isp = inode->i_security; + isp = smack_inode(inode); if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task) return 0; @@ -910,7 +910,7 @@ static void smack_inode_free_rcu(struct rcu_head *head) */ static void smack_inode_free_security(struct inode *inode) { - struct inode_smack *issp = inode->i_security; + struct inode_smack *issp = smack_inode(inode); /* * The inode may still be referenced in a path walk and @@ -938,7 +938,7 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, const char **name, void **value, size_t *len) { - struct inode_smack *issp = inode->i_security; + struct inode_smack *issp = smack_inode(inode); struct smack_known *skp = smk_of_current(); struct smack_known *isp = smk_of_inode(inode); struct smack_known *dsp = smk_of_inode(dir); @@ -1276,7 +1276,7 @@ static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { struct smack_known *skp; - struct inode_smack *isp = d_backing_inode(dentry)->i_security; + struct inode_smack *isp = smack_inode(d_backing_inode(dentry)); if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { isp->smk_flags |= SMK_INODE_TRANSMUTE; @@ -1357,7 +1357,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) if (rc != 0) return rc; - isp = d_backing_inode(dentry)->i_security; + isp = smack_inode(d_backing_inode(dentry)); /* * Don't do anything special for these. * XATTR_NAME_SMACKIPIN @@ -1632,7 +1632,7 @@ static int smack_mmap_file(struct file *file, if (unlikely(IS_PRIVATE(file_inode(file)))) return 0; - isp = file_inode(file)->i_security; + isp = smack_inode(file_inode(file)); if (isp->smk_mmap == NULL) return 0; sbsp = file_inode(file)->i_sb->s_security; @@ -1979,7 +1979,7 @@ static int smack_kernel_act_as(struct cred *new, u32 secid) static int smack_kernel_create_files_as(struct cred *new, struct inode *inode) { - struct inode_smack *isp = inode->i_security; + struct inode_smack *isp = smack_inode(inode); struct task_smack *tsp = smack_cred(new); tsp->smk_forked = isp->smk_inode; @@ -2179,7 +2179,7 @@ static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info, */ static void smack_task_to_inode(struct task_struct *p, struct inode *inode) { - struct inode_smack *isp = inode->i_security; + struct inode_smack *isp = smack_inode(inode); struct smack_known *skp = smk_of_task_struct(p); isp->smk_inode = skp; @@ -2642,7 +2642,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags) { struct smack_known *skp; - struct inode_smack *nsp = inode->i_security; + struct inode_smack *nsp = smack_inode(inode); struct socket_smack *ssp; struct socket *sock; int rc = 0; @@ -3250,7 +3250,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) if (inode == NULL) return; - isp = inode->i_security; + isp = smack_inode(inode); mutex_lock(&isp->smk_lock); /* @@ -4488,7 +4488,7 @@ static int smack_inode_copy_up(struct dentry *dentry, struct cred **new) /* * Get label from overlay inode and set it in create_sid */ - isp = d_inode(dentry->d_parent)->i_security; + isp = smack_inode(d_inode(dentry->d_parent)); skp = isp->smk_inode; tsp->smk_task = skp; *new = new_creds; @@ -4525,7 +4525,7 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode, /* * the attribute of the containing directory */ - isp = d_inode(dentry->d_parent)->i_security; + isp = smack_inode(d_inode(dentry->d_parent)); if (isp->smk_flags & SMK_INODE_TRANSMUTE) { rcu_read_lock(); -- cgit v1.2.3