Commit Graph

451 Commits

Author SHA1 Message Date
Jim Warner
bd7e1fb343 top: Prevent out-of-bounds writes in PUFF(). __Tweaked
This commit moves some overhead to the Batch mode path
where it's needed. And given the new 'else if' test we
can delete some now redundant logic in the other path.

Reference(s):
. original qualys patch
0117-top-Prevent-out-of-bounds-writes-in-PUFF.patch

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:20 +10:00
Jim Warner
8b94d11585 top: address 'show_special()' o-o-b read/write concern
This patch addresses a potential (but unlikely) buffer
overflow by reducing, if necessary, a memcpy length by
3 bytes to provide for an eol '\0' and 2 unused buffer
positions which also might receive the '\0' character.

[ note to future analysis tool: just because you see ]
[ binary data being manipulated in the routine, that ]
[ doesn't mean such function was passed binary data! ]

Reference(s):
. original qualys patch
0116-top-Fix-out-of-bounds-read-write-in-show_special.patch

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:20 +10:00
Jim Warner
085351a0ee top: prevent buffer overflow potential in all routines
Whereas an original patch (referenced below) addressed
some symptoms related to manually edited config files,
this solution deals with root causes. And it goes much
beyond any single top field by protecting all of top's
fields. Henceforth, a duplicated field is not allowed.

Reference(s):
. original qualys patch
0114-top-Prevent-buffer-overflow-in-calibrate_fields.patch

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:20 +10:00
Jim Warner
ffee26c370 top: check sortindx risk exposure (not treat symptoms)
Rather than validate the window's 'sortindx' each time
it was referenced (as was done in the patch below), we
now ensure the validity just once when the config file
is read. Thereafter, a running top will police bounds.

Reference(s):
. original qualys patch
0102-top-Check-sortindx.patch

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:20 +10:00
Jim Warner
e691cbaef4 top: other graph_cpus, graph_mems, and summ_mscale fix
This patch replaces an original patch referenced below
(omitted under this branch). We now validate variables
'graph_cpus', 'graph_mems' and 'summ_mscale' just once
at startup. Thereafter, top enforces the proper range.

[ we afford the same treatment to that 'task_mscale' ]
[ variable, which was ignored in the original patch. ]

Reference(s):
. original qualys patch
0099-top-Check-graph_cpus-graph_mems-and-summ_mscale.patch

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:20 +10:00
Jim Warner
4550e60144 top: Do not default to the cwd in configs_r... Tweaked
While it's only documented (so far) in commit text and
an occasional email I've tried to maintain some coding
standards primarily for reference/navigation purposes.
They also served, I felt, as useful mental challenges.

Someday I will get around to formerly documenting them
but in the meantime here are the ones for this commit:

. functions are grouped into logical (i hope) sections
. functions & sections are ordered to avoid prototypes
. function names are alphabetical within every section
. all functions & sections must be referenced in top.h

This patch just attempts to honor the above standards,
while also covering this new behavior in the man page.

[ please note that the net result of these 2 patches ]
[ is simply to avoid pathname truncations should our ]
[ limit of 1024 be exceeded. they do not have a role ]
[ in solving the 'local privilege escalation' issue. ]

[ and we can never prevent a user from setting their ]
[ HOME var to a directory writable by some attacker! ]

[ the only real protection for that CVE-2018-1122 is ]
[ those soon to be enhanced rcfile integrity checks, ]
[ achieved through several of the following patches. ]

Reference(s):
. original qualys patch
0097-top-Do-not-default-to-the-cwd-in-configs_read.patch

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
d099d0e5a1 0117-top: Prevent out-of-bounds writes in PUFF().
This patch prevents three problems:

1/ Because snprintf() returns "the number of characters (excluding the
terminating null byte) which would have been written to the final string
if enough space had been available", _eol may point past the end of _str
and write out-of-bounds (in Batch mode).

2/ _eol is never checked against _str, so "while (*(--_eol) == ' ');"
may point _eol below _str and write out-of-bounds (in Batch mode).

3/ Sanity-check Pseudo_row to protect the strcpy().
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
2ba9c569e5 0115-top: Harden calibrate_fields().
- Make sure i is at least 1 before "i - 1" and "--i".

- Initialize endpflg (to 0, as it was originally, since it is static)
  before the "for" loop (the "break" may leave endpflg uninitialized,
  for example).
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
6024543e79 0113-top: Impose a minimum on Screen_cols.
The safety of the critical function task_show() depends on the sanity of
Screen_cols. Just copy the tests on w_cols to Screen_cols (from the same
function adj_geometry()).
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
74e9d0afe1 0112-top: Prevent integer overflow in adj_geometry(). 2018-06-09 21:35:20 +10:00
Qualys Security Advisory
34b08eb8ac 0111-top: Limit Width_mode to SCREENMAX.
adj_geometry() limits to SCREENMAX too, but belt and suspenders, and
might as well tell the user about it.
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
2fabc50998 0110-top: Prevent integer overflows in config_file() and other_selection(). 2018-06-09 21:35:20 +10:00
Qualys Security Advisory
e1f419737f 0108-top: Always exit from sig_abexit().
The default action for SIGURG is to ignore the signal, for example.
This is very similar to the patch "ps/display.c: Always exit from
signal_handler()."
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
022cda9599 0107-top: Initialize struct sigaction in before(). 2018-06-09 21:35:20 +10:00
Qualys Security Advisory
2c461c8b05 0106-top: Fix snprintf() call in capsmk().
Replace "snprintf(msg, sizeof(pmt)" with "snprintf(msg, sizeof(msg)".
Luckily sizeof(pmt) == sizeof(msg), but fix it anyway.
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
f02fff62fb 0104-top: Initialize cp in task_show().
Found no problematic case at the moment, but this is a cheap
just-in-case.
2018-06-09 21:35:20 +10:00
Qualys Security Advisory
8b29093481 0103-top: Protect macro parameters.
---------------------------- adapted for newlib branch
. the 'isBUSY' macro is quite different under newlib

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-06-09 21:35:19 +10:00
Qualys Security Advisory
9cb8bee6a1 0101-top: Check width and col.
Otherwise they may lead to out-of-bounds writes (snprintf() returns the
number of characters which would have been written if enough space had
been available).

Also, make sure buf is null-terminated after COLPLUSCH has been written.
2018-06-09 21:35:19 +10:00
Qualys Security Advisory
766e31a2c3 0100-top: Check Rc.fixed_widest.
Otherwise it leads to crashes (for example, setting it to 2147483600 in
the configuration file segfaults top).
2018-06-09 21:35:19 +10:00
Qualys Security Advisory
0b0356de5c 0098-top: Check i when setting Curwin in config_file().
Otherwise it leads to out-of-bounds reads (and maybe writes).
2018-06-09 21:35:19 +10:00
Qualys Security Advisory
7c92bff183 0097-top: Do not default to the cwd in configs_read().
If the HOME environment variable is not set, or not absolute, use the
home directory returned by getpwuid(getuid()), if set and absolute
(instead of the cwd "."); otherwise, set p_home to NULL.

To keep the changes to a minimum, we rely on POSIX, which requires that
fopen() fails with ENOENT if the pathname (Rc_name) is an empty string.
This integrates well into the existing code, and makes write_rcfile()
work without a change.

Also, it makes the code in configs_read() easier to follow: only set and
use p_home if safe, and only set Rc_name if safe (in all the other cases
it is the empty string, and the fopen() calls fail). Plus, check for
snprintf() truncation (and if it happens, reset Rc_name to the empty
string).

Important note: top.1 should probably be updated, since it mentions the
fallback to the current working directory.
2018-06-09 21:35:19 +10:00
Qualys Security Advisory
54f02b7e11 0096-top: Fix double-fclose() in configs_read().
It happens only if RCFILE_NOERR is defined (it is not, by default).
2018-06-09 21:35:19 +10:00
Jim Warner
b2d7f620c0 top: show that truncation indicator ('+') consistently
With a little luck, this should be the final tweak for
our support of extra wide characters. Currently, those
characters don't always display the '+' indicator when
they've been truncated. Now, it should always be seen.

[ plus it's done a tad more efficiently via snprintf ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-03-03 17:53:10 +11:00
Jim Warner
2119750a51 top: change to exploit a newly added UID used at login
In addition to exploiting the login user ID provision,
the following miscellaneous changes are also included:

. unnecessary braces have been eliminated from an 'if'

. a comment with case EU_CPU: was corrected to 's_int'
and the associated block of code relocated accordingly

. case EU_CPN: wasn't shared with other enumerators so
reference to 'i' was changed to that actual enumerator

. case EU_SGN: wasn't shared with other enumerators so
reference to 'i' was changed to that actual enumerator

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
52f0ee2c41 top: update copyright dates in source and man document
Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
0f54ff181a top: try to avoid premature truncation indicator ('+')
Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
3aa348ad77 top: avoid potential truncation with 'Inspect' feature
As it turns out, that Ukrainian 'demo' text supporting
the '=' command was 152 bytes long, up from an English
version of 80 bytes. Unfortunately, the buffer used to
format all such strings was insufficient at 128 bytes.

Depending on the width of one's terminal, some strange
result could be experienced when a multi-byte sequence
was truncated. So, this just makes that buffer bigger.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
603129e60a top: allow translated field headers to determine width
After wrestling with extra wide characters, supporting
languages like zh_CN, sometimes default/minimum column
widths might force a truncation of translated headers.

So, this commit explores one way that such truncations
could be avoided. It is designed so as to have minimal
impact on existing code, ultimately affecting just one
function. But it's off by default via its own #define.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
7e1dfc12b6 top: an efficiency tweak to extra wide character logic
When I recently added extra wide character support for
locales like zh_CN, I didn't worry about some overhead
associated with the new calls to 'mbtowc' & 'wcwidth'.
That's because such overhead was usually incurred with
user interactions, not a normal iterative top display.

There was, however, one area where this overhead would
impact the normal iterative top mode - that's with the
Summary display. So I peeked at the glibc source code.

As it turns out, the costs of executing those 'mbtowc'
and 'wcwidth' functions were not at all insignificant.
So, this patch will avoid them in the vast majority of
instances, while still enabling extra wide characters.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
0192197198 top: standardize width of the %CPU & %MEM columns at 5
There is (should be) no justification for changing the
width of the percentage columns (%CPU, %MEM) depending
on the BOOST_PERCNT #define. So this patch will ensure
that both columns are fixed at their former maximum 5.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-19 20:33:59 +11:00
Jim Warner
6a5cd6d6fb top: respond to an additional library 'state' category
Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-12 20:58:31 +11:00
Jim Warner
264790d80d top: adapt utf8 logic to support extra wide characters
Back when top was refactored to support UTF-8 encoding
it was acknowledged that languages like zh_CN were not
supported. That was because a single 'character' might
require more than a single 'column' when it's printed.

Well I've now figured out how to accommodate languages
like that. My adaptation is represented in this patch.

[ and just in case someone wishes to avoid the extra ]
[ runtime costs, a #define OFF_XTRAWIDE is included. ]

Along the way, I've cleaned up some miscellaneous code
supporting the 'Inspect' feature so that the rightmost
screen column was always used rather than being blank.

[ interestingly, my xterm & urxvt terminal emulators ]
[ are able to split extra wide characters then print ]
[ 1/2 of such graphics in the last column. the gnome ]
[ terminal emulator does not duplicate such behavior ]
[ but prints 1 extra character in same width window. ]

Reference(s):
. Sep, 2017 - original utf8 support
commit 9773c56add

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-12 20:58:31 +11:00
Jim Warner
6f2e66969a top: tweak that recent enhancement to startup defaults
When the new approach for startup defaults was adopted
in the reference below, a file might be left open that
technically should be closed. This situation arises in
the unlikely event the #define RCFILE_NOERR is active.

Without that #define, the program will exit early thus
rendering the open file issue moot. However, even with
that #define there was no real harm with an open file.
It simply meant a 2nd FILE struct would have been used
when, or if, the rcfile was written via a 'W' command.

Anyway, this patch ensures such a file will be closed.

Reference(s):
. Dec, 2017 - /etc/topdefaultrc introduced
commit 55a42ae040

Signed-off-by: Jim Warner <james.warner@comcast.net>
2018-02-12 20:58:31 +11:00
Craig Small
91df65b9e7 docs: Document I idle state in ps and top
Linux 4.2 provided a new process state of I which is used for an idle
kernel thread. This new state means that kernel threads do not
contribute to the loadavg as they are no longer state D or S but I.

While both ps and top displayed this state, it wasn't documented in
either manual page until now.

References:
 https://bugs.debian.org/886967
 https://www.quora.com/What-does-mean-Linux-process-state-I-in-the-top-output
 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=80ed87c8a9ca0cad7ca66cf3bbdfb17559a66dcf
2018-01-13 11:25:59 +11:00
Jim Warner
55a42ae040 top: allow more flexible approach for startup defaults
Those references below offer more detail regarding the
default startup changes beginning with version 3.3.10.

It is important to remember that all such changes were
supposed to impact only new users or users who had not
saved the personal config file (via that 'W' command).
However, I introduced a bug wherein the rcfile was not
fully honored. This gave the changes a bad reputation.

That bug was corrected in release 3.3.11 but the issue
of default startup options keeps resurfacing. And it's
clear there's no consensus on what should be included.

Our --disable-modern-top configure option is of little
help since it remains an all-or-nothing approach. What
we need is an answer offering unlimited customization.
So, this commit will provide distribution packagers or
system administrators with a much more flexible way to
set their own preferred startup default configuration.

A new rcfile is being introduced: '/etc/topdefaultrc',
whose format/content is the same as a personal rcfile.
Thus once a 'proper' enterprise configuration has been
established and saved via 'W', it can be copied to the
/etc/ directory. Thereafter, startup in the absence of
a saved rcfile will use that configuration as default.

Now if a distribution packager or system administrator
wishes to expose their users to some of top's advanced
capabilities they can do so gradually. Perhaps setting
up graph mode for summary area task and memory display
while retaining the %CPU sort could be tried. Or maybe
showing colors, but better customized for a particular
terminal emulator. Such possibilities are now endless.

[ in exploiting this new capability, i hope that the ]
[ other windows (alt display mode) aren't overlooked ]

Reference(s):
. Sep, 2014 - Not fully honoring rcfile bug discussed
https://www.freelists.org/post/procps/top-saved-rcfile-bug
. Oct, 2014 - Attempt to defend new startup defaults
https://bugzilla.redhat.com/show_bug.cgi?id=1153049
. Jul, 2015 - Forest vs. %CPU views discussion
https://gitlab.com/procps-ng/procps/issues/6
. Oct, 2017 - Question the use of --disable-modern-top
https://bugzilla.redhat.com/show_bug.cgi?id=1499410
. Oct, 2017 - Forest vs. %CPU views discussion again
https://www.freelists.org/post/procps/Forest-mode-by-default-in-top-seems-a-bit-strange
. Dec, 2017 - Rehash of 3.3.10 startup defaults change
https://gitlab.com/procps-ng/procps/issues/78

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-12-23 17:44:34 +11:00
Jim Warner
0a502adfd0 top: let's exploit the new standardized errno handling
With the library having now normalized errno handling,
perhaps it is time at least one program took advantage
of it. So, instead of printing just a message with the
programs's line number, top will now also provide that
associated errno string text, compliments of strerror.

[ with those newlib functions returning NULL, we can ]
[ use errno directly in strerror. for the ones which ]
[ yield an int, all we need do is invert such return ]
[ values before passing it to the strerror function. ]

Reference(s):

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-12-23 17:44:34 +11:00
Jim Warner
71b3de01f2 top: miscellaneous changes to whitespace/comments only
[ ok, there's also 1 newly added #undef included too ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-12-23 17:44:34 +11:00
Jim Warner
fd77d86942 top: add and/or expand a couple more translation hints
After noticing that the 'uk' translation expanded what
was supposed to be a 3 line header into 5 lines, seems
appropriate to offer more guidance on max lines count.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-12-20 21:18:53 +11:00
Jim Warner
b5104910b1 top: stop neglecting potential utf8 field descriptions
And I thought those strange characters I saw with only
certain translations in Fields Management descriptions
were resulting from my terminal emulator deficiencies.

Turns out that ol' top wasn't addressing possibilities
of such descriptions ending with multi-byte sequences.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-14 21:48:00 +11:00
Jim Warner
a02a31f7e9 top: eliminate that potential vulnerability for TOCTOU
Initially, I was going to ignore that coverity warning
CID #177876. But, since top may be running SETUID it's
best if it can be avoided instead. The fix was simple.

We'll trade the access() call for a real fopen() call.
This time-of-check-time-of-use warning should go away.
------------------------------------------------------

When XDG support was originally introduced in top, the
author made a poor choice in access(). A real question
that needed asking was 'does the file exist'. However,
the question that was asked was 'can this real user ID
or this real group ID access the file'. Then, when the
fopen() is finally issued, top would use the effective
user ID or the effective group ID to access that file.

That's what opened the potential TOCTOU vulnerability,
which was important only if top was running SUID/SGID.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-14 21:48:00 +11:00
Jim Warner
d734d18f62 top: make 'utf8_justify' independent of non-utf8 logic
By eliminating the call to 'fmtmk', the 'utf8_justify'
function could more easily be used in libproc someday.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-14 21:48:00 +11:00
Jim Warner
474f4da5d1 top: utf8 utils should observe indentation conventions
Gosh, all this time we used indents of 4 spaces, not 3
spaces which were always the top standard indentation.

[ and we made our 'utf8_embody' a little more robust ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-14 21:48:00 +11:00
Jim Warner
3afadf56e4 top: ensure bug report suggestion agrees with man page
The top man page was changed back on 10/20/15, in that
commit shown below. There, freelists.org was suggested
as the bug reports recipient. But, the program was not
changed from the original Debian bug reports approach.

Reference(s):
commit b1f7b2a509

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-14 21:48:00 +11:00
Jim Warner
a74f604441 top: make the 'utf8_proper_col' routine more efficient
This patch better exploits short-circuit evaluation in
two 'if' tests. In every case, the 1st of 2 conditions
in each 'if' test must take place but it always proves
true with each iteration for 1 of the 'if' statements.
Thus, the 2nd condition will have to be evaluated too.

By reordering 2 tests in each 'if', we can ensure that
the 2nd condition will then be tested much less often.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-07 09:07:17 +11:00
Jim Warner
ca566ad554 top: make that 'make_str_utf8' function more efficient
Upon reflection, there was absolutely no justification
for that call to strlen() which was then followed by a
call to snprintf(). The latter provides this needed #.

[ also make that 'delta' value a little more visible ]
[ instead of hiding it at the end of a its code line ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-07 09:07:17 +11:00
Jim Warner
0154ffb280 top: ensured one translation hint agrees with template
Now that top can properly handle translated multi-byte
strings I've been reviewing translated efforts so far,
and weighing output against related translation hints.

In one case, a translation hint has not kept pace with
the current program state. In addition, that same hint
could be expanded to suggest translation alternatives.

[ frankly I never expected the translators to tackle ]
[ some of those 'special' strings. the task appeared ]
[ just too daunting. but they have done a great job! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-07 09:07:17 +11:00
Jim Warner
53a1b9650b top: again avoid multiple evaluation of macro argument
Before top was modified to exploit the new <pids> api,
there was protection in that task_show() makeVAR macro
to avoid multiple evaluation of this macro's argument.

But, in that commit referenced below, such a safeguard
was lost. This commit simply restores proper behavior.

Reference(s);
. offending change
commit 77dc22b910

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-07 09:07:17 +11:00
Jim Warner
e55016def5 top: when did scale_mem parm lose 'unsigned' qualifier
Well, for some strange unknown reason it happened in a
commit referenced below. But this patch reverts it and
puts this newlib scale_mem on par with the master guy.

[ a little more research reveals that it should have ]
[ been reverted in the 2nd commit shown. that's when ]
[ types were fixed after XTRA_PROCPS_DEBUG was used. ]

Reference(s):
. when 'unsigned' qualifier lost
commit 911083bf76
. when 'unsigned' qualifier not restored
commit 105058ae2d
. when XTRA_PROCPS_DEBUG validation introduced
commit e3270d463d

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-07 09:07:17 +11:00
Jim Warner
335c070c8d top: improve the translator hint regarding field width
Reference(s):
https://www.freelists.org/post/procps/Does-COMMAND-really-have-to-be-at-most-7-characters,2

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-07 09:07:17 +11:00
Jim Warner
1bc25e920a top: correct an insidious occasional truncation buglet
With the help of our Swedish translator, hopefully the
final buglet has now been vanquished in the multi-byte
translation support. This one was a real nasty bugger.

Although it didn't occur with every terminal emulator,
occasionally random text lines were being chopped off.

As it turns out, those terminals were blameless. There
were two separate places in top's show_special routine
where potential multi-byte sequences were inadequately
addressed. Solution: exploit existing utf-8 functions.

[ it also became apparent that the translation hints ]
[ in the top_nls module were deficient. so a special ]
[ caution was added regarding the final line of txt. ]

Reference(s):
https://gitlab.com/procps-ng/procps/issues/68

Signed-off-by: Jim Warner <james.warner@comcast.net>
2017-10-02 22:23:13 +11:00