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Diffstat (limited to 'fs/proc/root.c')
-rw-r--r--fs/proc/root.c131
1 files changed, 100 insertions, 31 deletions
diff --git a/fs/proc/root.c b/fs/proc/root.c
index cdbe9293ea55..ffebed1999e5 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -32,21 +32,86 @@
struct proc_fs_context {
struct pid_namespace *pid_ns;
unsigned int mask;
- int hidepid;
+ enum proc_hidepid hidepid;
int gid;
+ enum proc_pidonly pidonly;
};
enum proc_param {
Opt_gid,
Opt_hidepid,
+ Opt_subset,
};
static const struct fs_parameter_spec proc_fs_parameters[] = {
fsparam_u32("gid", Opt_gid),
- fsparam_u32("hidepid", Opt_hidepid),
+ fsparam_string("hidepid", Opt_hidepid),
+ fsparam_string("subset", Opt_subset),
{}
};
+static inline int valid_hidepid(unsigned int value)
+{
+ return (value == HIDEPID_OFF ||
+ value == HIDEPID_NO_ACCESS ||
+ value == HIDEPID_INVISIBLE ||
+ value == HIDEPID_NOT_PTRACEABLE);
+}
+
+static int proc_parse_hidepid_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct proc_fs_context *ctx = fc->fs_private;
+ struct fs_parameter_spec hidepid_u32_spec = fsparam_u32("hidepid", Opt_hidepid);
+ struct fs_parse_result result;
+ int base = (unsigned long)hidepid_u32_spec.data;
+
+ if (param->type != fs_value_is_string)
+ return invalf(fc, "proc: unexpected type of hidepid value\n");
+
+ if (!kstrtouint(param->string, base, &result.uint_32)) {
+ if (!valid_hidepid(result.uint_32))
+ return invalf(fc, "proc: unknown value of hidepid - %s\n", param->string);
+ ctx->hidepid = result.uint_32;
+ return 0;
+ }
+
+ if (!strcmp(param->string, "off"))
+ ctx->hidepid = HIDEPID_OFF;
+ else if (!strcmp(param->string, "noaccess"))
+ ctx->hidepid = HIDEPID_NO_ACCESS;
+ else if (!strcmp(param->string, "invisible"))
+ ctx->hidepid = HIDEPID_INVISIBLE;
+ else if (!strcmp(param->string, "ptraceable"))
+ ctx->hidepid = HIDEPID_NOT_PTRACEABLE;
+ else
+ return invalf(fc, "proc: unknown value of hidepid - %s\n", param->string);
+
+ return 0;
+}
+
+static int proc_parse_subset_param(struct fs_context *fc, char *value)
+{
+ struct proc_fs_context *ctx = fc->fs_private;
+
+ while (value) {
+ char *ptr = strchr(value, ',');
+
+ if (ptr != NULL)
+ *ptr++ = '\0';
+
+ if (*value != '\0') {
+ if (!strcmp(value, "pid")) {
+ ctx->pidonly = PROC_PIDONLY_ON;
+ } else {
+ return invalf(fc, "proc: unsupported subset option - %s\n", value);
+ }
+ }
+ value = ptr;
+ }
+
+ return 0;
+}
+
static int proc_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
struct proc_fs_context *ctx = fc->fs_private;
@@ -63,10 +128,13 @@ static int proc_parse_param(struct fs_context *fc, struct fs_parameter *param)
break;
case Opt_hidepid:
- ctx->hidepid = result.uint_32;
- if (ctx->hidepid < HIDEPID_OFF ||
- ctx->hidepid > HIDEPID_INVISIBLE)
- return invalfc(fc, "hidepid value must be between 0 and 2.\n");
+ if (proc_parse_hidepid_param(fc, param))
+ return -EINVAL;
+ break;
+
+ case Opt_subset:
+ if (proc_parse_subset_param(fc, param->string) < 0)
+ return -EINVAL;
break;
default:
@@ -77,26 +145,33 @@ static int proc_parse_param(struct fs_context *fc, struct fs_parameter *param)
return 0;
}
-static void proc_apply_options(struct super_block *s,
+static void proc_apply_options(struct proc_fs_info *fs_info,
struct fs_context *fc,
- struct pid_namespace *pid_ns,
struct user_namespace *user_ns)
{
struct proc_fs_context *ctx = fc->fs_private;
if (ctx->mask & (1 << Opt_gid))
- pid_ns->pid_gid = make_kgid(user_ns, ctx->gid);
+ fs_info->pid_gid = make_kgid(user_ns, ctx->gid);
if (ctx->mask & (1 << Opt_hidepid))
- pid_ns->hide_pid = ctx->hidepid;
+ fs_info->hide_pid = ctx->hidepid;
+ if (ctx->mask & (1 << Opt_subset))
+ fs_info->pidonly = ctx->pidonly;
}
static int proc_fill_super(struct super_block *s, struct fs_context *fc)
{
- struct pid_namespace *pid_ns = get_pid_ns(s->s_fs_info);
+ struct proc_fs_context *ctx = fc->fs_private;
struct inode *root_inode;
+ struct proc_fs_info *fs_info;
int ret;
- proc_apply_options(s, fc, pid_ns, current_user_ns());
+ fs_info = kzalloc(sizeof(*fs_info), GFP_KERNEL);
+ if (!fs_info)
+ return -ENOMEM;
+
+ fs_info->pid_ns = get_pid_ns(ctx->pid_ns);
+ proc_apply_options(fs_info, fc, current_user_ns());
/* User space would break if executables or devices appear on proc */
s->s_iflags |= SB_I_USERNS_VISIBLE | SB_I_NOEXEC | SB_I_NODEV;
@@ -106,6 +181,7 @@ static int proc_fill_super(struct super_block *s, struct fs_context *fc)
s->s_magic = PROC_SUPER_MAGIC;
s->s_op = &proc_sops;
s->s_time_gran = 1;
+ s->s_fs_info = fs_info;
/*
* procfs isn't actually a stacking filesystem; however, there is
@@ -113,7 +189,7 @@ static int proc_fill_super(struct super_block *s, struct fs_context *fc)
* top of it
*/
s->s_stack_depth = FILESYSTEM_MAX_STACK_DEPTH;
-
+
/* procfs dentries and inodes don't require IO to create */
s->s_shrink.seeks = 0;
@@ -140,19 +216,17 @@ static int proc_fill_super(struct super_block *s, struct fs_context *fc)
static int proc_reconfigure(struct fs_context *fc)
{
struct super_block *sb = fc->root->d_sb;
- struct pid_namespace *pid = sb->s_fs_info;
+ struct proc_fs_info *fs_info = proc_sb_info(sb);
sync_filesystem(sb);
- proc_apply_options(sb, fc, pid, current_user_ns());
+ proc_apply_options(fs_info, fc, current_user_ns());
return 0;
}
static int proc_get_tree(struct fs_context *fc)
{
- struct proc_fs_context *ctx = fc->fs_private;
-
- return get_tree_keyed(fc, proc_fill_super, ctx->pid_ns);
+ return get_tree_nodev(fc, proc_fill_super);
}
static void proc_fs_context_free(struct fs_context *fc)
@@ -188,22 +262,17 @@ static int proc_init_fs_context(struct fs_context *fc)
static void proc_kill_sb(struct super_block *sb)
{
- struct pid_namespace *ns;
+ struct proc_fs_info *fs_info = proc_sb_info(sb);
- ns = (struct pid_namespace *)sb->s_fs_info;
- if (ns->proc_self)
- dput(ns->proc_self);
- if (ns->proc_thread_self)
- dput(ns->proc_thread_self);
- kill_anon_super(sb);
+ if (fs_info->proc_self)
+ dput(fs_info->proc_self);
- /* Make the pid namespace safe for the next mount of proc */
- ns->proc_self = NULL;
- ns->proc_thread_self = NULL;
- ns->pid_gid = GLOBAL_ROOT_GID;
- ns->hide_pid = 0;
+ if (fs_info->proc_thread_self)
+ dput(fs_info->proc_thread_self);
- put_pid_ns(ns);
+ kill_anon_super(sb);
+ put_pid_ns(fs_info->pid_ns);
+ kfree(fs_info);
}
static struct file_system_type proc_fs_type = {