sh: Fix pathname expansion with quoted slashes like *\/.

These are git commits 36f0fa8fcbc8c7b2b194addd29100fb40e73e4e9 and
d6d06ff5c2ea0fa44becc5ef4340e5f2f15073e4 in dash.

Because this is the first code I'm importing from dash to expand.c, add the
Herbert Xu copyright notice which is in dash's expand.c.

When pathname expanding *\/, the CTLESC representing the quoted state was
erroneously taken as part of the * pathname component. This CTLESC was then
seen by the pattern matching code as escaping the '\0' terminating the
string.

The code is slightly different because dash converts the CTLESC characters
to backslashes and removes all the other CTL* characters to allow
substituting glob(3).

The effect of the bug was also slightly different from dash (where nothing
matched at all). Because a CTLESC can escape a '\0' in some way, whether
files were included despite the bug depended on memory that should not be
read. In particular, on many machines /*\/ expanded to a strict subset of
what /*/ expanded to.

Example:
  echo /*"/null"

This should print /dev/null, not /*/null.

PR:		bin/146378
Obtained from:	dash
This commit is contained in:
Jilles Tjoelker 2010-05-11 23:19:28 +00:00
parent 2583690e62
commit 4710b07ecf
2 changed files with 46 additions and 9 deletions

View File

@ -1,6 +1,8 @@
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1997-2005
* Herbert Xu <herbert@gondor.apana.org.au>. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
@ -1150,10 +1152,11 @@ expmeta(char *enddir, char *name)
struct dirent *dp;
int atend;
int matchdot;
int esc;
metaflag = 0;
start = name;
for (p = name ; ; p++) {
for (p = name; esc = 0, *p; p += esc + 1) {
if (*p == '*' || *p == '?')
metaflag = 1;
else if (*p == '[') {
@ -1178,12 +1181,14 @@ expmeta(char *enddir, char *name)
break;
else if (*p == CTLQUOTEMARK)
continue;
else if (*p == CTLESC)
p++;
if (*p == '/') {
if (metaflag)
break;
start = p + 1;
else {
if (*p == CTLESC)
esc++;
if (p[esc] == '/') {
if (metaflag)
break;
start = p + esc + 1;
}
}
}
if (metaflag == 0) { /* we've reached the end of the file name */
@ -1229,7 +1234,8 @@ expmeta(char *enddir, char *name)
atend = 1;
} else {
atend = 0;
*endname++ = '\0';
*endname = '\0';
endname += esc + 1;
}
matchdot = 0;
p = start;
@ -1257,7 +1263,7 @@ expmeta(char *enddir, char *name)
}
closedir(dirp);
if (! atend)
endname[-1] = '/';
endname[-esc - 1] = esc ? CTLESC : '/';
}

View File

@ -0,0 +1,31 @@
# $FreeBSD$
failures=0
check() {
testcase=$1
expect=$2
eval "set -- $testcase"
actual="$*"
if [ "$actual" != "$expect" ]; then
failures=$((failures+1))
printf '%s\n' "For $testcase, expected $expect actual $actual"
fi
}
set -e
T=$(mktemp -d ${TMPDIR:-/tmp}/sh-test.XXXXXX)
trap 'rm -rf $T' 0
cd -P $T
mkdir testdir testdir2 'testdir/*' 'testdir/?' testdir/a testdir/b testdir2/b
mkdir testdir2/.c
touch testf 'testdir/*/1' 'testdir/?/1' testdir/a/1 testdir/b/1 testdir2/b/.a
check '*\/' 'testdir/ testdir2/'
check '"testdir/"*"/1"' 'testdir/*/1 testdir/?/1 testdir/a/1 testdir/b/1'
check '"testdir/"*"/"*' 'testdir/*/1 testdir/?/1 testdir/a/1 testdir/b/1'
check '"testdir/"*\/*' 'testdir/*/1 testdir/?/1 testdir/a/1 testdir/b/1'
check '"testdir"*"/"*"/"*' 'testdir/*/1 testdir/?/1 testdir/a/1 testdir/b/1'
exit $((failures != 0))