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diff --git a/man5/proc.5 b/man5/proc.5 deleted file mode 100644 index ce072ee..0000000 --- a/man5/proc.5 +++ /dev/null @@ -1,259 +0,0 @@ -.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com> -.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com> -.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org> -.\" -.\" SPDX-License-Identifier: GPL-3.0-or-later -.\" -.TH proc 5 2023-10-31 "Linux man-pages 6.7" -.SH NAME -proc \- process information, system information, and sysctl pseudo-filesystem -.SH DESCRIPTION -The -.B proc -filesystem is a pseudo-filesystem which provides an interface to -kernel data structures. -It is commonly mounted at -.IR /proc . -Typically, it is mounted automatically by the system, -but it can also be mounted manually using a command such as: -.P -.in +4n -.EX -mount \-t proc proc /proc -.EE -.in -.P -Most of the files in the -.B proc -filesystem are read-only, -but some files are writable, allowing kernel variables to be changed. -.\" -.SS Mount options -The -.B proc -filesystem supports the following mount options: -.TP -.BR hidepid "=\fIn\fP (since Linux 3.3)" -.\" commit 0499680a42141d86417a8fbaa8c8db806bea1201 -This option controls who can access the information in -.IR /proc/ pid -directories. -The argument, -.IR n , -is one of the following values: -.RS -.TP 4 -0 -Everybody may access all -.IR /proc/ pid -directories. -This is the traditional behavior, -and the default if this mount option is not specified. -.TP -1 -Users may not access files and subdirectories inside any -.IR /proc/ pid -directories but their own (the -.IR /proc/ pid -directories themselves remain visible). -Sensitive files such as -.IR /proc/ pid /cmdline -and -.IR /proc/ pid /status -are now protected against other users. -This makes it impossible to learn whether any user is running a -specific program -(so long as the program doesn't otherwise reveal itself by its behavior). -.\" As an additional bonus, since -.\" .IR /proc/[pid]/cmdline -.\" is inaccessible for other users, -.\" poorly written programs passing sensitive information via -.\" program arguments are now protected against local eavesdroppers. -.TP -2 -As for mode 1, but in addition the -.IR /proc/ pid -directories belonging to other users become invisible. -This means that -.IR /proc/ pid -entries can no longer be used to discover the PIDs on the system. -This doesn't hide the fact that a process with a specific PID value exists -(it can be learned by other means, for example, by "kill \-0 $PID"), -but it hides a process's UID and GID, -which could otherwise be learned by employing -.BR stat (2) -on a -.IR /proc/ pid -directory. -This greatly complicates an attacker's task of gathering -information about running processes (e.g., discovering whether -some daemon is running with elevated privileges, -whether another user is running some sensitive program, -whether other users are running any program at all, and so on). -.RE -.TP -.BR gid "=\fIgid\fP (since Linux 3.3)" -.\" commit 0499680a42141d86417a8fbaa8c8db806bea1201 -Specifies the ID of a group whose members are authorized to -learn process information otherwise prohibited by -.B hidepid -(i.e., users in this group behave as though -.I /proc -was mounted with -.IR hidepid=0 ). -This group should be used instead of approaches such as putting -nonroot users into the -.BR sudoers (5) -file. -.\" -.SS Overview -Underneath -.IR /proc , -there are the following general groups of files and subdirectories: -.TP -.IR /proc/ "pid subdirectories" -Each one of these subdirectories contains files and subdirectories -exposing information about the process with the corresponding process ID. -.IP -Underneath each of the -.IR /proc/ pid -directories, a -.I task -subdirectory contains subdirectories of the form -.IR task/ tid, -which contain corresponding information about each of the threads -in the process, where -.I tid -is the kernel thread ID of the thread. -.IP -The -.IR /proc/ pid -subdirectories are visible when iterating through -.I /proc -with -.BR getdents (2) -(and thus are visible when one uses -.BR ls (1) -to view the contents of -.IR /proc ). -.TP -.IR /proc/ "tid subdirectories" -Each one of these subdirectories contains files and subdirectories -exposing information about the thread with the corresponding thread ID. -The contents of these directories are the same as the corresponding -.IR /proc/ pid /task/ tid -directories. -.IP -The -.IR /proc/ tid -subdirectories are -.I not -visible when iterating through -.I /proc -with -.BR getdents (2) -(and thus are -.I not -visible when one uses -.BR ls (1) -to view the contents of -.IR /proc ). -.TP -.I /proc/self -When a process accesses this magic symbolic link, -it resolves to the process's own -.IR /proc/ pid -directory. -.TP -.I /proc/thread\-self -When a thread accesses this magic symbolic link, -it resolves to the process's own -.IR /proc/self/task/ tid -directory. -.TP -.I /proc/[a\-z]* -Various other files and subdirectories under -.I /proc -expose system-wide information. -.P -All of the above are described in more detail below. -.\" -.\" .SH FILES -.\" FIXME Describe /proc/[pid]/sessionid -.\" commit 1e0bd7550ea9cf474b1ad4c6ff5729a507f75fdc -.\" CONFIG_AUDITSYSCALL -.\" Added in Linux 2.6.25; read-only; only readable by real UID -.\" -.\" FIXME Describe /proc/[pid]/sched -.\" Added in Linux 2.6.23 -.\" CONFIG_SCHED_DEBUG, and additional fields if CONFIG_SCHEDSTATS -.\" Displays various scheduling parameters -.\" This file can be written, to reset stats -.\" The set of fields exposed by this file have changed -.\" significantly over time. -.\" commit 43ae34cb4cd650d1eb4460a8253a8e747ba052ac -.\" -.\" FIXME Describe /proc/[pid]/schedstats and -.\" /proc/[pid]/task/[tid]/schedstats -.\" Added in Linux 2.6.9 -.\" CONFIG_SCHEDSTATS -.\" FIXME Document /proc/sched_debug (since Linux 2.6.23) -.\" See also /proc/[pid]/sched -.\" FIXME 2.6.13 seems to have /proc/vmcore implemented; document this -.\" See Documentation/kdump/kdump.txt -.\" commit 666bfddbe8b8fd4fd44617d6c55193d5ac7edb29 -.\" Needs CONFIG_VMCORE -.\" -.SH NOTES -Many files contain strings (e.g., the environment and command line) -that are in the internal format, -with subfields terminated by null bytes (\[aq]\e0\[aq]). -When inspecting such files, you may find that the results are more readable -if you use a command of the following form to display them: -.P -.in +4n -.EX -.RB "$" " cat \fIfile\fP | tr \[aq]\e000\[aq] \[aq]\en\[aq]" -.EE -.in -.\" .SH ACKNOWLEDGEMENTS -.\" The material on /proc/sys/fs and /proc/sys/kernel is closely based on -.\" kernel source documentation files written by Rik van Riel. -.SH SEE ALSO -.BR cat (1), -.BR dmesg (1), -.BR find (1), -.BR free (1), -.BR htop (1), -.BR init (1), -.BR ps (1), -.BR pstree (1), -.BR tr (1), -.BR uptime (1), -.BR chroot (2), -.BR mmap (2), -.BR readlink (2), -.BR syslog (2), -.BR slabinfo (5), -.BR sysfs (5), -.BR hier (7), -.BR namespaces (7), -.BR time (7), -.BR arp (8), -.BR hdparm (8), -.BR ifconfig (8), -.BR lsmod (8), -.BR lspci (8), -.BR mount (8), -.BR netstat (8), -.BR procinfo (8), -.BR route (8), -.BR sysctl (8) -.P -The Linux kernel source files: -.IR Documentation/filesystems/proc.rst , -.IR Documentation/admin\-guide/sysctl/fs.rst , -.IR Documentation/admin\-guide/sysctl/kernel.rst , -.IR Documentation/admin\-guide/sysctl/net.rst , -and -.IR Documentation/admin\-guide/sysctl/vm.rst . |