Commit Graph

70 Commits

Author SHA1 Message Date
Ian Lepore
97603f1da2 Use explicit_bzero() when cleaning values out of the kernel environment.
Sometimes the values contain geli passphrases being communicated from
loader(8) to the kernel, and some day the compiler may decide to start
eliding calls to memset() for a pointer which is not dereferenced again
before being passed to free().
2018-04-10 22:57:56 +00:00
Pedro F. Giffuni
8a36da99de sys/kern: adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:20:12 +00:00
Warner Losh
15be49f5a1 Create wrappers for uint64_t and int64_t for the tunables. While not
strictly necessary, it is more convenient.
2016-04-15 03:09:55 +00:00
Ian Lepore
85143dd18d Allow a dynamic env to override a compiled-in static env by passing in the
override indication in the env data.

Submitted by:	bde
2016-02-21 18:35:01 +00:00
Ian Lepore
69dcb7e771 Make the 'env' directive described in config(5) work on all architectures,
providing compiled-in static environment data that is used instead of any
data passed in from a boot loader.

Previously 'env' worked only on i386 and arm xscale systems, because it
required the MD startup code to examine the global envmode variable and
decide whether to use static_env or an environment obtained from the boot
loader, and set the global kern_envp accordingly.  Most startup code wasn't
doing so.  Making things even more complex, some mips startup code uses an
alternate scheme that involves calling init_static_kenv() to pass an empty
buffer and its size, then uses a series of kern_setenv() calls to populate
that buffer.

Now all MD startup code calls init_static_kenv(), and that routine provides
a single point where envmode is checked and the decision is made whether to
use the compiled-in static_kenv or the values provided by the MD code.

The routine also continues to serve its original purpose for mips; if a
non-zero buffer size is passed the routine installs the empty buffer ready
to accept kern_setenv() values.  Now if the size is zero, the provided buffer
full of existing env data is installed.  A NULL pointer can be passed if the
boot loader provides no env data; this allows the static env to be installed
if envmode is set to do so.

Most of the work here is a near-mechanical change to call the init function
instead of directly setting kern_envp.  A notable exception is in xen/pv.c;
that code was originally installing a buffer full of preformatted env data
along with its non-zero size (like mips code does), which would have allowed
kern_setenv() calls to wipe out the preformatted data.  Now it passes a zero
for the size so that the buffer of data it installs is treated as
non-writeable.
2016-01-02 02:53:48 +00:00
Xin LI
2735a91d93 Test if 'env' is NULL before doing memset() and strlen(),
the caller may pass NULL to freeenv().
2014-10-23 18:23:50 +00:00
Colin Percival
b9f6af45a5 Avoid leaking data from the kernel environment: When we convert the
initial static environment to a dynamic one, zero the static environment
buffer, and zero individual values when kern_unsetenv and freeenv are
called.

Tested by:	kmoore (VM memory dump + grep)
Tested by:	cperciva (kernel panic dump + grep)
2014-10-22 23:35:32 +00:00
Davide Italiano
2be111bf7d Follow up to r225617. In order to maximize the re-usability of kernel code
in userland rename in-kernel getenv()/setenv() to kern_setenv()/kern_getenv().
This fixes a namespace collision with libc symbols.

Submitted by:   kmacy
Tested by:      make universe
2014-10-16 18:04:43 +00:00
Alexander Motin
915f2b7c89 Make getenv_*() functions and respectively TUNABLE_*_FETCH() macros not
allocate memory and so not require sleepable environment.  getenv() has
already used on-stack temporary storage, so just use it more rationally.
getenv_string() receives buffer as argument, so don't need another one.
2013-11-01 10:32:33 +00:00
Warner Losh
11c601447d r249408 and r249436 cause a NULL pointer dereference on the CUBIEBOARD
since it doesn't set the kernel envrionment at all. Work around this
by making sure kern_envp is non-NULL before dereferencing it.
2013-04-16 22:09:08 +00:00
Jayachandran C.
f46206c270 Fix changes made in r249408.
In some cases, kern_envp is set by the architecture code and env_pos does
not contain the length of the static kernel environment. In these cases
r249408 causes the kernel to discard the environment.

Fix this by updating the check for empty static env to *kern_envp != '\0'

Reported by:	np@
2013-04-13 07:23:37 +00:00
Jayachandran C.
15f9c9ed69 Fix kenv behavior when there is no static environment
In case where there are no static kernel environment entries, the
function init_dynamic_kenv() adds an incorrect entry at position 0 of
the dynamic kernel environment. This in turn causes kenv(1) to print
and empty list even though there are dynamic entries added later.

Fix this by checking env_pos in init_dynamic_kenv() and adding dynamic
entries only if there are static entries.
2013-04-12 15:58:53 +00:00
Jaakko Heinonen
2f0ac2593b Reserve room for the terminating NUL when setting or getting kernel
environment variables. KENV_MNAMELEN and KENV_MVALLEN doesn't include
space for the terminating NUL.
2012-08-14 19:16:30 +00:00
Kip Macy
8451d0dd78 In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00
Jaakko Heinonen
f53edc909e In init_dynamic_kenv(), ignore environment strings exceeding the
KENV_MNAMELEN + 1 + KENV_MVALLEN + 1 length limit to avoid buffer
overflow in getenv(). Currenly loader(8) doesn't limit the length of
environment strings.

PR:		kern/132104
MFC after:	1 month
2011-05-23 16:40:44 +00:00
Jaakko Heinonen
852bee75b7 To avoid duplicated warning, move WITNESS_WARN() added in r221597 to the
branch which doesn't call malloc(9).

Suggested by:	kib
2011-05-07 17:59:07 +00:00
Jaakko Heinonen
816c203937 Add WITNESS_WARN() to getenv() to explicitly note that the function may
sleep. This helps to expose bugs when the requested environment variable
doesn't exist.
2011-05-07 11:10:58 +00:00
Warner Losh
eae8e367c5 Merge change r198561 from projects/mips to head:
r198561 | thompsa | 2009-10-28 15:25:22 -0600 (Wed, 28 Oct 2009) | 4 lines
Allow a scratch buffer to be set in order to be able to use setenv() while
booting, before dynamic kenv is running. A few platforms implement their own
scratch+sprintf handling to save data from the boot environment.
2010-01-10 22:34:18 +00:00
Robert Watson
bcf11e8d00 Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with:	pjd
2009-06-05 14:55:22 +00:00
Colin Percival
3f935cf342 Correctly sanity-check timer IDs. [SA-09:06]
Limit the size of malloced buffer when dumping environment
variables. [EN-09:01]

Approved by:	so (cperciva)
Approved by:	re (kensmith)
Security:	FreeBSD-SA-09:06.ktimer
Errata:		FreeBSD-EN-09:01.kenv
2009-03-23 00:00:50 +00:00
Pawel Jakub Dawidek
7f41115ef6 Implement the following macros for completeness:
SYSCTL_QUAD()
	SYSCTL_ADD_QUAD()
	TUNABLE_QUAD()
	TUNABLE_QUAD_FETCH()

Now we can use 64bit tunables on 32bit systems.
2008-07-21 15:05:25 +00:00
Robert Watson
30d239bc4c Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
Dag-Erling Smørgrav
d302c56d9b I don't know what I was smoking when I wrote these three years ago; the
return value is an error code, hence always an int.

While I'm here, add getenv_uint() for completeness.
2007-10-13 11:30:19 +00:00
Robert Watson
873fbcd776 Further system call comment cleanup:
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
  "syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
2007-03-05 13:10:58 +00:00
Robert Watson
acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
Robert Watson
aed5570872 Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h.  sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA
2006-10-22 11:52:19 +00:00
Scott Long
e3546a7549 Use a sleep mutex instead of an sx lock for the kernel environment. This
allows greater flexibility for drivers that want to query the environment.

Reviewed by: jhb, mux
2006-07-09 21:42:58 +00:00
Alexander Leidinger
a8f47039c7 Fix memory leak introduced in previous revision.
Discussed with:	phk
2006-03-15 19:23:08 +00:00
Poul-Henning Kamp
c8d7706e75 Ignore kenv strings which overflow the room we have, rather than pretend
we have room for them.
2006-03-09 09:29:41 +00:00
David Xu
2b7182c6b7 Reorder statements to avoid accessing unknown memory.
In theory, invoking kenv with very long string can panic
kernel.
2005-09-26 14:14:55 +00:00
Alexander Leidinger
3904769ba8 Add bounds checking to the setenv part of the kernel environment.
This has no security implications since only root is allowed to use
kenv(1) (and corrupt the kernel memory after adding too much variables
previous to this commit).

This is based upon the PR [1] mentioned below, but extended to check both
bounds (in case of an overflow of the counting variable) and to comply
to the style of the function. An overflow of the counting variable
shouldn't happen after adding the check for the upper bound, but better
safe than sorry (in case some other function in the kernel overwrites
random memory).

An interested soul may want to add a printf to notify root in case the
bounds are hit.

Also allocate KENV_SIZE+1 entries (the array is NULL-terminated), since
the comment for KENV_SIZE says it's the maximum number of environment
strings. [2]

PR:		83687 [1]
Submitted by:	Harry Coin <harrycoin@qconline.com> [1]
Submitted by:	Ariff Abdullah <skywizard@MyBSD.org.my> [2]
2005-07-31 10:28:35 +00:00
Dag-Erling Smørgrav
628b83cd08 My addled brains didn't realize that since vtp points into value, we
can't freeenv(value) before we're done inspecting vtp[0].

Tested by:	Anish Mistry <mistry.7@osu.edu>
2005-03-09 12:16:45 +00:00
Dag-Erling Smørgrav
f3301d15f1 Teach getenv_quad() to recognize k/m/g/t suffixes in both lower- and
upper-case.  This means (almost) all tunables now support those suffixes.
2005-03-05 15:52:12 +00:00
Poul-Henning Kamp
c711aea6ca Make a bunch of malloc types static.
Found by:	src/tools/tools/kernxref
2005-02-10 12:02:37 +00:00
Dag-Erling Smørgrav
ed3fdd0e3a Retire TUNABLE_QUAD_*. 2004-11-08 18:22:22 +00:00
Dag-Erling Smørgrav
b0e1e474f7 Add TUNABLE_LONG and TUNABLE_ULONG, and use the latter for the
hw.pci.host_mem_start tunable.  Add comments to TUNABLE_INT and
TUNABLE_QUAD recommending against their use.

MFC after:	3 weeks
2004-10-31 15:50:33 +00:00
David Schultz
06afcd9d10 If the buffer supplied to kenv(KENV_DUMP, ...) isn't big enough,
return the number of bytes needed instead of 0.  The manpage claims
that we do this anyway.
2004-04-28 01:27:33 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Warner Losh
a163d034fa Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
Alfred Perlstein
44956c9863 Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
Alfred Perlstein
b80521fee5 remove syscallarg().
Suggested by: peter
2002-12-14 02:07:32 +00:00
Alfred Perlstein
d1e405c5ce SCARGS removal take II. 2002-12-14 01:56:26 +00:00
Alfred Perlstein
bc9e75d7ca Backout removal SCARGS, the code freeze is only "selectively" over. 2002-12-13 22:41:47 +00:00
Alfred Perlstein
0bbe7292e1 Remove SCARGS.
Reviewed by: md5
2002-12-13 22:27:25 +00:00
Robert Watson
e686e5ae91 Add MAC checks for various kenv() operations: dump, get, set, unset,
permitting MAC policies to limit access to the kernel environment.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-01 20:46:53 +00:00
Robert Drehmel
e80fb43467 Use strlcpy() instead of strncpy() to copy NUL terminated strings
for safety and consistency.
2002-10-17 20:03:38 +00:00
Peter Wemm
6692ac6644 Cosmetic tweaks. Try and keep the style more consistent, catch some stray
whitespace and update a comment.
2002-05-01 02:51:50 +00:00
Bruce Evans
2c900f6451 Fixed some longstanding bugs in _getenv_static():
- malformed environment strings (ones without an '=') were not rejected.
  There shouldn't be any of these, but when the static environment is
  empty it always begins with one of these; this one should be considered
  as the terminator after the end of the environment, but it isn't.
- the comparison of the name being looked up with the name in the
  environment was fuzzy -- only the characters up to the length of the
  latter were compared, so _getenv_static("foobar") matched "foo=..."
  in the environment and everything matched "" in the empty environment.

MFC after:	3 days
2002-04-25 20:25:15 +00:00
Maxime Henrion
b48a4280fc Avoid calling malloc() or free() while holding the
kenv lock.

Reviewed by:	jake
2002-04-17 17:51:10 +00:00
Maxime Henrion
d786139c76 Rework the kernel environment subsystem. We now convert the static
environment needed at boot time to a dynamic subsystem when VM is
up.  The dynamic kernel environment is protected by an sx lock.

This adds some new functions to manipulate the kernel environment :
freeenv(), setenv(), unsetenv() and testenv().  freeenv() has to be
called after every getenv() when you have finished using the string.
testenv() only tests if an environment variable is present, and
doesn't require a freeenv() call. setenv() and unsetenv() are self
explanatory.

The kenv(2) syscall exports these new functionalities to userland,
mainly for kenv(1).

Reviewed by:	peter
2002-04-17 13:06:36 +00:00