diff options
| -rw-r--r-- | fs/proc/generic.c | 9 | ||||
| -rw-r--r-- | fs/proc/inode.c | 6 | ||||
| -rw-r--r-- | fs/proc/root.c | 33 | ||||
| -rw-r--r-- | include/linux/proc_fs.h | 7 |
4 files changed, 55 insertions, 0 deletions
diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 4ed6dabdf6ff..2f9fa179194d 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -269,6 +269,11 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry, struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { + struct proc_fs_info *fs_info = proc_sb_info(dir->i_sb); + + if (fs_info->pidonly == PROC_PIDONLY_ON) + return ERR_PTR(-ENOENT); + return proc_lookup_de(dir, dentry, PDE(dir)); } @@ -325,6 +330,10 @@ int proc_readdir_de(struct file *file, struct dir_context *ctx, int proc_readdir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); + struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb); + + if (fs_info->pidonly == PROC_PIDONLY_ON) + return 1; return proc_readdir_de(file, ctx, PDE(inode)); } diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 9c756531282a..0d5e68fa842f 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -173,6 +173,8 @@ static int proc_show_options(struct seq_file *seq, struct dentry *root) seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, fs_info->pid_gid)); if (fs_info->hide_pid != HIDEPID_OFF) seq_printf(seq, ",hidepid=%u", fs_info->hide_pid); + if (fs_info->pidonly != PROC_PIDONLY_OFF) + seq_printf(seq, ",subset=pid"); return 0; } @@ -463,6 +465,7 @@ proc_reg_get_unmapped_area(struct file *file, unsigned long orig_addr, static int proc_reg_open(struct inode *inode, struct file *file) { + struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb); struct proc_dir_entry *pde = PDE(inode); int rv = 0; typeof_member(struct proc_ops, proc_open) open; @@ -476,6 +479,9 @@ static int proc_reg_open(struct inode *inode, struct file *file) return rv; } + if (fs_info->pidonly == PROC_PIDONLY_ON) + return -ENOENT; + /* * Ensure that * 1) PDE's ->release hook will be called no matter what diff --git a/fs/proc/root.c b/fs/proc/root.c index 8f23b951d685..baff006a918f 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -34,16 +34,19 @@ struct proc_fs_context { unsigned int mask; int hidepid; int gid; + int 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("subset", Opt_subset), {} }; @@ -55,6 +58,29 @@ static inline int valid_hidepid(unsigned int value) value == HIDEPID_NOT_PTRACEABLE); } +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; @@ -76,6 +102,11 @@ static int proc_parse_param(struct fs_context *fc, struct fs_parameter *param) ctx->hidepid = result.uint_32; break; + case Opt_subset: + if (proc_parse_subset_param(fc, param->string) < 0) + return -EINVAL; + break; + default: return -EINVAL; } @@ -94,6 +125,8 @@ static void proc_apply_options(struct proc_fs_info *fs_info, fs_info->pid_gid = make_kgid(user_ns, ctx->gid); if (ctx->mask & (1 << Opt_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) diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index 5bdc117ae947..8bc31ba5cd9c 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -50,12 +50,19 @@ enum { HIDEPID_NOT_PTRACEABLE = 4, /* Limit pids to only ptraceable pids */ }; +/* definitions for proc mount option pidonly */ +enum { + PROC_PIDONLY_OFF = 0, + PROC_PIDONLY_ON = 1, +}; + struct proc_fs_info { struct pid_namespace *pid_ns; struct dentry *proc_self; /* For /proc/self */ struct dentry *proc_thread_self; /* For /proc/thread-self */ kgid_t pid_gid; int hide_pid; + int pidonly; }; static inline struct proc_fs_info *proc_sb_info(struct super_block *sb) |