Mercurial > vim
view src/vimtutor @ 33262:6eac4f616293 v9.0.1899
patch 9.0.1899: potential buffer overflow in PBYTE macro
Commit: https://github.com/vim/vim/commit/ffb13674d1af1c90beb229867ec989e4fb232df3
Author: Christian Brabandt <cb@256bit.org>
Date: Fri Sep 15 20:22:02 2023 +0200
patch 9.0.1899: potential buffer overflow in PBYTE macro
Problem: potential buffer overflow in PBYTE macro
Solution: Check returned memline length
closes: #13083
the PBYTE macro is used to put byte c at a position lp of the returned
memline. However, in case of unexpected errors ml_get_buf() may return
either "???" or an empty line in which case it is quite likely that we
are causing a buffer overrun.
Therefore, switch the macro PBYTE (which is only used in ops.c anyhow)
to a function, that verifies that we will only try to access within the
given length of the buffer.
Also, since the macro is only used in ops.c, move the definition from
macros.h to ops.c
Signed-off-by: Christian Brabandt <cb@256bit.org>
author | Christian Brabandt <cb@256bit.org> |
---|---|
date | Fri, 15 Sep 2023 20:30:07 +0200 |
parents | d4faa2c5211b |
children |
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#!/bin/sh # Start Vim on a copy of the tutor file. # Usage: vimtutor [-g] [xx] # Where optional argument -g starts vimtutor in gvim (GUI) instead of vim. # and xx is a language code like "es" or "nl". # When an argument is given, it tries loading that tutor. # When this fails or no argument was given, it tries using 'v:lang' # When that also fails, it uses the English version. # Vim could be called "vim" or "vi". Also check for "vimN", for people who # have Vim installed with its version number. # We anticipate up to a future Vim 8.1 version :-). seq="vim vim81 vim80 vim8 vim74 vim73 vim72 vim71 vim70 vim7 vim6 vi" if test "$1" = "-g"; then # Try to use the GUI version of Vim if possible, it will fall back # on Vim if Gvim is not installed. seq="gvim gvim81 gvim80 gvim8 gvim74 gvim73 gvim72 gvim71 gvim70 gvim7 gvim6 $seq" shift fi xx=$1 export xx # We need a temp file for the copy. First try using a standard command. tmp="${TMPDIR-/tmp}" TUTORCOPY=`mktemp $tmp/tutorXXXXXX || tempfile -p tutor || echo none` # If the standard commands failed then create a directory to put the copy in. # That is a secure way to make a temp file. if test "$TUTORCOPY" = none; then tmpdir=$tmp/vimtutor$$ OLD_UMASK=`umask` umask 077 getout=no mkdir $tmpdir || getout=yes umask $OLD_UMASK if test $getout = yes; then echo "Could not create directory for tutor copy, exiting." exit 1 fi TUTORCOPY=$tmpdir/tutorcopy touch $TUTORCOPY TODELETE=$tmpdir else TODELETE=$TUTORCOPY fi export TUTORCOPY # remove the copy of the tutor on exit trap "rm -rf $TODELETE" 0 1 2 3 9 11 13 15 for i in $seq; do testvim=$(which $i 2>/dev/null) if test -f "$testvim"; then VIM=$i break fi done # When no Vim version was found fall back to "vim", you'll get an error message # below. if test -z "$VIM"; then VIM=vim fi # Use Vim to copy the tutor, it knows the value of $VIMRUNTIME # The script tutor.vim tells Vim which file to copy $VIM -f -u NONE -c 'so $VIMRUNTIME/tutor/tutor.vim' # Start vim without any .vimrc, set 'nocompatible' and 'showcmd' $VIM -f -u NONE -c "set nocp showcmd" "$TUTORCOPY"