Mercurial > vim
view READMEdir/README_os390.txt @ 33811:06219b3bdaf3 v9.0.2121
patch 9.0.2121: [security]: use-after-free in ex_substitute
Commit: https://github.com/vim/vim/commit/26c11c56888d01e298cd8044caf860f3c26f57bb
Author: Christian Brabandt <cb@256bit.org>
Date: Wed Nov 22 21:26:41 2023 +0100
patch 9.0.2121: [security]: use-after-free in ex_substitute
Problem: [security]: use-after-free in ex_substitute
Solution: always allocate memory
closes: #13552
A recursive :substitute command could cause a heap-use-after free in Vim
(CVE-2023-48706).
The whole reproducible test is a bit tricky, I can only reproduce this
reliably when no previous substitution command has been used yet
(which is the reason, the test needs to run as first one in the
test_substitute.vim file) and as a combination of the `:~` command
together with a :s command that contains the special substitution atom `~\=`
which will make use of a sub-replace special atom and calls a vim script
function.
There was a comment in the existing :s code, that already makes the
`sub` variable allocate memory so that a recursive :s call won't be able
to cause any issues here, so this was known as a potential problem
already. But for the current test-case that one does not work, because
the substitution does not start with `\=` but with `~\=` (and since
there does not yet exist a previous substitution atom, Vim will simply
increment the `sub` pointer (which then was not allocated dynamically)
and later one happily use a sub-replace special expression (which could
then free the `sub` var).
The following commit fixes this, by making the sub var always using
allocated memory, which also means we need to free the pointer whenever
we leave the function. Since sub is now always an allocated variable,
we also do no longer need the sub_copy variable anymore, since this one
was used to indicated when sub pointed to allocated memory (and had
therefore to be freed on exit) and when not.
Github Security Advisory:
https://github.com/vim/vim/security/advisories/GHSA-c8qm-x72m-q53q
Signed-off-by: Christian Brabandt <cb@256bit.org>
author | Christian Brabandt <cb@256bit.org> |
---|---|
date | Wed, 22 Nov 2023 22:15:05 +0100 |
parents | 93c715c63a4a |
children | 4635e43f2c6f |
line wrap: on
line source
README_os390.txt for version 9.0 of Vim: Vi IMproved. This readme explains how to build Vim on z/OS. Formerly called OS/390. See "README.txt" for general information about Vim. Most likely there are not many users out there using Vim on z/OS. So chances are good, that some bugs are still undiscovered. Getting the source to z/OS: ========================== First get the source code in one big tar file and ftp it a binary to z/OS. If the tar file is initially compressed with gzip (tar.gz) or bzip2 (tar.bz2) uncompress it on your PC, as these tools are (most likely) not available on the mainframe. To reduce the size of the tar file you might compress it into a zip file. On z/OS Unix you might have the command "jar" from java to uncompress a zip. Use: jar xvf <zip file name> Unpack the tar file on z/OS with pax -o from=ISO8859-1,to=IBM-1047 -rf vim.tar Note: The Vim source contains a few bitmaps etc which will be destroyed by this command, but these files are not needed on zOS (at least not for the console version). Compiling: ========== Vim can be compiled with or without GUI support. For 7.4 only the compilation without GUI was tested. Below is a section about compiling with X11 but this is from an earlier version of Vim. Console only: ------------- If you build VIM without X11 support, compiling and building is nearly straightforward. Change to the vim directory and do: # Don't use c89! # Allow intermixing of compiler options and files. $ export CC=cc $ export _CC_CCMODE=1 $./configure --with-features=normal --without-x --enable-gui=no $ cd src $ make There may be warnings: - include files not found (libc, sys/param.h, ...) - Redeclaration of ... differs from ... -- just ignore them. $ make test This will produce lots of garbage on your screen (including error messages). Don't worry. If the test stops at one point in vim (might happen in test 11), just press :q! Expected test failures: 11: If you don't have gzip installed 24: test of backslash sequences in regexp are ASCII dependent 42: Multibyte is not supported on z/OS 55: ASCII<->EBCDIC sorting 57: ASCII<->EBCDIC sorting 58: Spell checking is not supported with EBCDIC 71: Blowfish encryption doesn't work $ make install With X11: --------- WARNING: This instruction was not tested with Vim 7.4 or later. There are two ways for building VIM with X11 support. The first way is simple and results in a big executable (~13 Mb), the second needs a few additional steps and results in a much smaller executable (~4.5 Mb). These examples assume you want Motif. The easy way: $ export CC=cc $ export _CC_CCMODE=1 $ ./configure --enable-max-features --enable-gui=motif $ cd src $ make With this VIM is linked statically with the X11 libraries. The smarter way: Make VIM as described above. Then create a file named 'link.sed' with the following content (see src/link.390): s/-lXext *//g s/-lXmu *//g s/-lXm */\/usr\/lib\/Xm.x /g s/-lX11 */\/usr\/lib\/X11.x /g s/-lXt *//g s/-lSM */\/usr\/lib\/SM.x /g s/-lICE */\/usr\/lib\/ICE.x /g Then do: $ rm vim $ make Now Vim is linked with the X11-DLLs. See the Makefile and the file link.sh on how link.sed is used.