new helper: security_sb_eat_lsm_opts()

combination of alloc_secdata(), security_sb_copy_data(),
security_sb_parse_opt_str() and free_secdata().

Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2018-11-17 12:09:18 -05:00
parent c039bc3c24
commit f5c0c26d90
6 changed files with 20 additions and 77 deletions

View File

@ -1461,20 +1461,7 @@ out:
static int parse_security_options(char *orig_opts,
struct security_mnt_opts *sec_opts)
{
char *secdata = NULL;
int ret = 0;
secdata = alloc_secdata();
if (!secdata)
return -ENOMEM;
ret = security_sb_copy_data(orig_opts, secdata);
if (ret) {
free_secdata(secdata);
return ret;
}
ret = security_sb_parse_opts_str(secdata, sec_opts);
free_secdata(secdata);
return ret;
return security_sb_eat_lsm_opts(orig_opts, sec_opts);
}
static int setup_security_options(struct btrfs_fs_info *fs_info,

View File

@ -2312,16 +2312,7 @@ static int do_remount(struct path *path, int ms_flags, int sb_flags,
security_init_mnt_opts(&opts);
if (data && !(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)) {
char *secdata = alloc_secdata();
if (!secdata)
return -ENOMEM;
err = security_sb_copy_data(data, secdata);
if (err) {
free_secdata(secdata);
return err;
}
err = security_sb_parse_opts_str(secdata, &opts);
free_secdata(secdata);
err = security_sb_eat_lsm_opts(data, &opts);
if (err)
return err;
}

View File

@ -1206,7 +1206,7 @@ static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
static int nfs_parse_mount_options(char *raw,
struct nfs_parsed_mount_data *mnt)
{
char *p, *string, *secdata;
char *p, *string;
int rc, sloppy = 0, invalid_option = 0;
unsigned short protofamily = AF_UNSPEC;
unsigned short mountfamily = AF_UNSPEC;
@ -1217,20 +1217,10 @@ static int nfs_parse_mount_options(char *raw,
}
dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
secdata = alloc_secdata();
if (!secdata)
goto out_nomem;
rc = security_sb_copy_data(raw, secdata);
rc = security_sb_eat_lsm_opts(raw, &mnt->lsm_opts);
if (rc)
goto out_security_failure;
rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
if (rc)
goto out_security_failure;
free_secdata(secdata);
while ((p = strsep(&raw, ",")) != NULL) {
substring_t args[MAX_OPT_ARGS];
unsigned long option;
@ -1682,7 +1672,6 @@ out_nomem:
printk(KERN_INFO "NFS: not enough memory to parse option\n");
return 0;
out_security_failure:
free_secdata(secdata);
printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
return 0;
}

View File

@ -1252,18 +1252,7 @@ mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
security_init_mnt_opts(&opts);
if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) {
char *secdata = alloc_secdata();
if (!secdata)
return ERR_PTR(-ENOMEM);
error = security_sb_copy_data(data, secdata);
if (error) {
free_secdata(secdata);
return ERR_PTR(error);
}
error = security_sb_parse_opts_str(secdata, &opts);
free_secdata(secdata);
error = security_sb_eat_lsm_opts(data, &opts);
if (error)
return ERR_PTR(error);
}

View File

@ -248,7 +248,7 @@ void security_bprm_committing_creds(struct linux_binprm *bprm);
void security_bprm_committed_creds(struct linux_binprm *bprm);
int security_sb_alloc(struct super_block *sb);
void security_sb_free(struct super_block *sb);
int security_sb_copy_data(char *orig, char *copy);
int security_sb_eat_lsm_opts(char *options, struct security_mnt_opts *opts);
int security_sb_remount(struct super_block *sb, struct security_mnt_opts *opts);
int security_sb_kern_mount(struct super_block *sb, int flags,
struct security_mnt_opts *opts);
@ -556,7 +556,8 @@ static inline int security_sb_alloc(struct super_block *sb)
static inline void security_sb_free(struct super_block *sb)
{ }
static inline int security_sb_copy_data(char *orig, char *copy)
static inline int security_sb_eat_lsm_opts(char *options,
struct security_mnt_opts *opts)
{
return 0;
}
@ -1823,28 +1824,5 @@ static inline void security_bpf_prog_free(struct bpf_prog_aux *aux)
#endif /* CONFIG_SECURITY */
#endif /* CONFIG_BPF_SYSCALL */
#ifdef CONFIG_SECURITY
static inline char *alloc_secdata(void)
{
return (char *)get_zeroed_page(GFP_KERNEL);
}
static inline void free_secdata(void *secdata)
{
free_page((unsigned long)secdata);
}
#else
static inline char *alloc_secdata(void)
{
return (char *)1;
}
static inline void free_secdata(void *secdata)
{ }
#endif /* CONFIG_SECURITY */
#endif /* ! __LINUX_SECURITY_H */

View File

@ -384,11 +384,20 @@ void security_sb_free(struct super_block *sb)
call_void_hook(sb_free_security, sb);
}
int security_sb_copy_data(char *orig, char *copy)
int security_sb_eat_lsm_opts(char *options, struct security_mnt_opts *opts)
{
return call_int_hook(sb_copy_data, 0, orig, copy);
char *s = (char *)get_zeroed_page(GFP_KERNEL);
int err;
if (!s)
return -ENOMEM;
err = call_int_hook(sb_copy_data, 0, options, s);
if (!err)
err = call_int_hook(sb_parse_opts_str, 0, s, opts);
free_page((unsigned long)s);
return err;
}
EXPORT_SYMBOL(security_sb_copy_data);
EXPORT_SYMBOL(security_sb_eat_lsm_opts);
int security_sb_remount(struct super_block *sb,
struct security_mnt_opts *opts)