zsh/SOURCES/0001-zsh-5.5.1-CVE-2018-050...

149 lines
4.7 KiB
Diff

From ddb6c5b4c0ab9c6a7404112d367f0c7cc400ceec Mon Sep 17 00:00:00 2001
From: Anthony Sottile <asottile@umich.edu>
Date: Mon, 3 Sep 2018 14:39:25 +0000
Subject: [PATCH] CVE-2018-0502, CVE-2018-13259: Fix two security issues in
shebang line parsing.
See NEWS for more information.
Patch by Anthony Sottile and Buck Evan.
Upstream-commit: 1c4c7b6a4d17294df028322b70c53803a402233d
Signed-off-by: Kamil Dudka <kdudka@redhat.com>
---
Etc/FAQ.yo | 2 +-
Src/exec.c | 36 ++++++++++++++++++++----------------
Test/A05execution.ztst | 22 ++++++++++++++++++++++
3 files changed, 43 insertions(+), 17 deletions(-)
diff --git a/Etc/FAQ.yo b/Etc/FAQ.yo
index 72ff7fa..8552fe7 100644
--- a/Etc/FAQ.yo
+++ b/Etc/FAQ.yo
@@ -306,7 +306,7 @@ sect(On what machines will it run?)
sect(What's the latest version?)
- Zsh 5.5.1 is the latest production version. For details of all the
+ Zsh 5.6 is the latest production version. For details of all the
changes, see the NEWS file in the source distribution.
A beta of the next version is sometimes available. Development of zsh is
diff --git a/Src/exec.c b/Src/exec.c
index 216057a..0908a1a 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -453,7 +453,7 @@ execcursh(Estate state, int do_exec)
/* execve after handling $_ and #! */
-#define POUNDBANGLIMIT 64
+#define POUNDBANGLIMIT 128
/**/
static int
@@ -494,18 +494,20 @@ zexecve(char *pth, char **argv, char **newenvp)
if ((fd = open(pth, O_RDONLY|O_NOCTTY)) >= 0) {
argv0 = *argv;
*argv = pth;
- execvebuf[0] = '\0';
+ memset(execvebuf, '\0', POUNDBANGLIMIT + 1);
ct = read(fd, execvebuf, POUNDBANGLIMIT);
close(fd);
if (ct >= 0) {
- if (execvebuf[0] == '#') {
- if (execvebuf[1] == '!') {
- for (t0 = 0; t0 != ct; t0++)
- if (execvebuf[t0] == '\n')
- break;
+ if (ct >= 2 && execvebuf[0] == '#' && execvebuf[1] == '!') {
+ for (t0 = 0; t0 != ct; t0++)
+ if (execvebuf[t0] == '\n')
+ break;
+ if (t0 == ct)
+ zerr("%s: bad interpreter: %s: %e", pth,
+ execvebuf + 2, eno);
+ else {
while (inblank(execvebuf[t0]))
execvebuf[t0--] = '\0';
- execvebuf[POUNDBANGLIMIT] = '\0';
for (ptr = execvebuf + 2; *ptr && *ptr == ' '; ptr++);
for (ptr2 = ptr; *ptr && *ptr != ' '; ptr++);
if (eno == ENOENT) {
@@ -514,10 +516,16 @@ zexecve(char *pth, char **argv, char **newenvp)
*ptr = '\0';
if (*ptr2 != '/' &&
(pprog = pathprog(ptr2, NULL))) {
- argv[-2] = ptr2;
- argv[-1] = ptr + 1;
- winch_unblock();
- execve(pprog, argv - 2, newenvp);
+ if (ptr == execvebuf + t0 + 1) {
+ argv[-1] = ptr2;
+ winch_unblock();
+ execve(pprog, argv - 1, newenvp);
+ } else {
+ argv[-2] = ptr2;
+ argv[-1] = ptr + 1;
+ winch_unblock();
+ execve(pprog, argv - 2, newenvp);
+ }
}
zerr("%s: bad interpreter: %s: %e", pth, ptr2,
eno);
@@ -532,10 +540,6 @@ zexecve(char *pth, char **argv, char **newenvp)
winch_unblock();
execve(ptr2, argv - 1, newenvp);
}
- } else if (eno == ENOEXEC) {
- argv[-1] = "sh";
- winch_unblock();
- execve("/bin/sh", argv - 1, newenvp);
}
} else if (eno == ENOEXEC) {
for (t0 = 0; t0 != ct; t0++)
diff --git a/Test/A05execution.ztst b/Test/A05execution.ztst
index 0804691..fb39d05 100644
--- a/Test/A05execution.ztst
+++ b/Test/A05execution.ztst
@@ -12,7 +12,14 @@
print '#!/bin/sh\necho This is dir2' >dir2/tstcmd
+ print -n '#!sh\necho This is slashless' >tstcmd-slashless
+ print -n '#!echo foo\necho This is arg' >tstcmd-arg
+ print '#!xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxnyyy' >tstcmd-interp-too-long
+ print '#!/bin/sh\necho should not execute; exit 1' >xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxn
+
chmod 755 tstcmd dir1/tstcmd dir2/tstcmd
+ chmod 755 tstcmd-slashless tstcmd-arg tstcmd-interp-too-long
+ chmod 755 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxn
%test
./tstcmd
@@ -33,6 +40,21 @@
0:path (2)
>This is top
+ PATH=/bin:${ZTST_testdir}/command.tmp/ tstcmd-slashless
+0:path (3)
+>This is slashless
+
+ PATH=/bin:${ZTST_testdir}/command.tmp tstcmd-arg
+0:path (4)
+*>foo */command.tmp/tstcmd-arg
+
+ path=(/bin ${ZTST_testdir}/command.tmp/)
+ tstcmd-interp-too-long 2>&1; echo "status $?"
+ path=($storepath)
+0:path (5)
+*>*tstcmd-interp-too-long: bad interpreter: x*xn: no such file or directory
+>status 127
+
functst() { print $# arguments:; print -l $*; }
functst "Eines Morgens" "als Gregor Samsa"
functst ""
--
2.17.1