linux/fs/hfsplus/options.c
Aditya Garg 9f2b5debc0 hfsplus: fix bug causing custom uid and gid being unable to be assigned with mount
Despite specifying UID and GID in mount command, the specified UID and GID
were not being assigned. This patch fixes this issue.

Link: https://lkml.kernel.org/r/C0264BF5-059C-45CF-B8DA-3A3BD2C803A2@live.com
Signed-off-by: Aditya Garg <gargaditya08@live.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-11 19:30:20 -08:00

244 lines
5.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/hfsplus/options.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Option parsing
*/
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/parser.h>
#include <linux/nls.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include "hfsplus_fs.h"
enum {
opt_creator, opt_type,
opt_umask, opt_uid, opt_gid,
opt_part, opt_session, opt_nls,
opt_nodecompose, opt_decompose,
opt_barrier, opt_nobarrier,
opt_force, opt_err
};
static const match_table_t tokens = {
{ opt_creator, "creator=%s" },
{ opt_type, "type=%s" },
{ opt_umask, "umask=%o" },
{ opt_uid, "uid=%u" },
{ opt_gid, "gid=%u" },
{ opt_part, "part=%u" },
{ opt_session, "session=%u" },
{ opt_nls, "nls=%s" },
{ opt_decompose, "decompose" },
{ opt_nodecompose, "nodecompose" },
{ opt_barrier, "barrier" },
{ opt_nobarrier, "nobarrier" },
{ opt_force, "force" },
{ opt_err, NULL }
};
/* Initialize an options object to reasonable defaults */
void hfsplus_fill_defaults(struct hfsplus_sb_info *opts)
{
if (!opts)
return;
opts->creator = HFSPLUS_DEF_CR_TYPE;
opts->type = HFSPLUS_DEF_CR_TYPE;
opts->umask = current_umask();
opts->uid = current_uid();
opts->gid = current_gid();
opts->part = -1;
opts->session = -1;
}
/* convert a "four byte character" to a 32 bit int with error checks */
static inline int match_fourchar(substring_t *arg, u32 *result)
{
if (arg->to - arg->from != 4)
return -EINVAL;
memcpy(result, arg->from, 4);
return 0;
}
int hfsplus_parse_options_remount(char *input, int *force)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int token;
if (!input)
return 1;
while ((p = strsep(&input, ",")) != NULL) {
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case opt_force:
*force = 1;
break;
default:
break;
}
}
return 1;
}
/* Parse options from mount. Returns 0 on failure */
/* input is the options passed to mount() as a string */
int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int tmp, token;
if (!input)
goto done;
while ((p = strsep(&input, ",")) != NULL) {
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case opt_creator:
if (match_fourchar(&args[0], &sbi->creator)) {
pr_err("creator requires a 4 character value\n");
return 0;
}
break;
case opt_type:
if (match_fourchar(&args[0], &sbi->type)) {
pr_err("type requires a 4 character value\n");
return 0;
}
break;
case opt_umask:
if (match_octal(&args[0], &tmp)) {
pr_err("umask requires a value\n");
return 0;
}
sbi->umask = (umode_t)tmp;
break;
case opt_uid:
if (match_int(&args[0], &tmp)) {
pr_err("uid requires an argument\n");
return 0;
}
sbi->uid = make_kuid(current_user_ns(), (uid_t)tmp);
if (!uid_valid(sbi->uid)) {
pr_err("invalid uid specified\n");
return 0;
} else {
set_bit(HFSPLUS_SB_UID, &sbi->flags);
}
break;
case opt_gid:
if (match_int(&args[0], &tmp)) {
pr_err("gid requires an argument\n");
return 0;
}
sbi->gid = make_kgid(current_user_ns(), (gid_t)tmp);
if (!gid_valid(sbi->gid)) {
pr_err("invalid gid specified\n");
return 0;
} else {
set_bit(HFSPLUS_SB_GID, &sbi->flags);
}
break;
case opt_part:
if (match_int(&args[0], &sbi->part)) {
pr_err("part requires an argument\n");
return 0;
}
break;
case opt_session:
if (match_int(&args[0], &sbi->session)) {
pr_err("session requires an argument\n");
return 0;
}
break;
case opt_nls:
if (sbi->nls) {
pr_err("unable to change nls mapping\n");
return 0;
}
p = match_strdup(&args[0]);
if (p)
sbi->nls = load_nls(p);
if (!sbi->nls) {
pr_err("unable to load nls mapping \"%s\"\n",
p);
kfree(p);
return 0;
}
kfree(p);
break;
case opt_decompose:
clear_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
break;
case opt_nodecompose:
set_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
break;
case opt_barrier:
clear_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags);
break;
case opt_nobarrier:
set_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags);
break;
case opt_force:
set_bit(HFSPLUS_SB_FORCE, &sbi->flags);
break;
default:
return 0;
}
}
done:
if (!sbi->nls) {
/* try utf8 first, as this is the old default behaviour */
sbi->nls = load_nls("utf8");
if (!sbi->nls)
sbi->nls = load_nls_default();
if (!sbi->nls)
return 0;
}
return 1;
}
int hfsplus_show_options(struct seq_file *seq, struct dentry *root)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(root->d_sb);
if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
seq_show_option_n(seq, "creator", (char *)&sbi->creator, 4);
if (sbi->type != HFSPLUS_DEF_CR_TYPE)
seq_show_option_n(seq, "type", (char *)&sbi->type, 4);
seq_printf(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask,
from_kuid_munged(&init_user_ns, sbi->uid),
from_kgid_munged(&init_user_ns, sbi->gid));
if (sbi->part >= 0)
seq_printf(seq, ",part=%u", sbi->part);
if (sbi->session >= 0)
seq_printf(seq, ",session=%u", sbi->session);
if (sbi->nls)
seq_printf(seq, ",nls=%s", sbi->nls->charset);
if (test_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags))
seq_puts(seq, ",nodecompose");
if (test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
seq_puts(seq, ",nobarrier");
return 0;
}