Re: [PATCH] make sure internal temp files are user readable and writeable

[Martijn Dekker <martijn@xxxxxxxx>]

Op 26-03-18 om 19:37 schreef Martijn Dekker:
> Op 26-03-18 om 19:00 schreef Stephane Chazelas:
>> Thanks. See also 42446
>> (https://www.zsh.org/mla/workers/2018/msg00252.html)
>> with other suggested options.
> 
> Ah yes, sorry, forgot you'd already brought it up here.

Re-reading that, my thought is: while option 2 might be nice to have,
option 4 is the simple, obvious and immediate fix, so that's the one I'm
capable of providing -- especially with a release imminent.

If you'd like to have a go at implementing option 2, so much the better.

>> There I mentioned the potential need to block signals between
>> the time the umask is changed temporarily and when it's restored
>> (to avoid traps running with the wrong umask (0177 instead of
>> the user's requested one)).
> 
> Good point.
> 
> Please consider my patch withdrawn.

Today was apparently not my best day. Since that function was already
blocking (a.k.a. queueing) signals to do its thing, of course my patch
was trivial to fix. Take 2.

- M.

diff --git a/Src/utils.c b/Src/utils.c
index 6517e15..4660142 100644
--- a/Src/utils.c
+++ b/Src/utils.c
@@ -2177,10 +2177,12 @@ gettempfile(const char *prefix, int use_heap, char **tempname)
 {
     char *fn;
     int fd;
+    mode_t old_umask;
 #if HAVE_MKSTEMP
     char *suffix = prefix ? ".XXXXXX" : "XXXXXX";
 
     queue_signals();
+    old_umask = umask(0177);
     if (!prefix && !(prefix = getsparam("TMPPREFIX")))
 	prefix = DEFAULT_TMPPREFIX;
     if (use_heap)
@@ -2198,6 +2200,7 @@ gettempfile(const char *prefix, int use_heap, char **tempname)
     int failures = 0;
 
     queue_signals();
+    old_umask = umask(0177);
     do {
 	if (!(fn = gettempname(prefix, use_heap))) {
 	    fd = -1;
@@ -2212,6 +2215,7 @@ gettempfile(const char *prefix, int use_heap, char **tempname)
 #endif
     *tempname = fn;
 
+    umask(old_umask);
     unqueue_signals();
     return fd;
 }
diff --git a/Test/A04redirect.ztst b/Test/A04redirect.ztst
index ef7ddb2..b5b65cf 100644
--- a/Test/A04redirect.ztst
+++ b/Test/A04redirect.ztst
@@ -667,3 +667,12 @@
 0:Redirect in the middle of assignments
 >b
 >d
+
+  umask 0777
+  cat <<'  HERE'
+  look ma, no permissions
+  HERE
+  cat <<<"it's a miracle"
+0:Here-{string,document}s succeed with restrictive umask
+>  look ma, no permissions
+>it's a miracle