Re: fuser(1): Fix pledge when `u' flag is used

[Sebastien Marie]

On Fri, Jan 01, 2016 at 10:29:08PM -0500, Michael Reed wrote:
> Hi,
> 
> `fuser -u -c /' doesn't seem to work for me:
> 
>     fuser(28663): syscall 33 "getpw"
> 
> The patch below fixes my issue.  The pledge condition was already a bit
> long, so I just switched to snprintf(3); not sure what's normally done
> in such situations.
> 

When possible, we try to keep the `if conditions' and don't construct
pledge promises strings by hand. Else it would make pledge promises not
grep-able.

Could you confirm this diff resolves your problem ?

Comments ?
-- 
Sebastien Marie


Index: fstat.c
===================================================================
RCS file: /cvs/src/usr.bin/fstat/fstat.c,v
retrieving revision 1.85
diff -u -p -r1.85 fstat.c
--- fstat.c     30 Dec 2015 19:02:12 -0000      1.85
+++ fstat.c     2 Jan 2016 12:58:31 -0000
@@ -276,7 +276,18 @@ main(int argc, char *argv[])
                errx(1, "%s", kvm_geterr(kd));
 
        if (fuser) {
-               if (sflg) { /* fuser might call kill(2) */
+               /**
+                * fuser
+                *  uflg: need "getpw"
+                *  sflg: need "proc" (might call kill(2))
+                */
+               if (uflg && sflg) {
+                       if (pledge("stdio rpath getpw proc", NULL) == -1)
+                               err(1, "pledge");
+               } else if (uflg) {
+                       if (pledge("stdio rpath getpw", NULL) == -1)
+                               err(1, "pledge");
+               } else if (sflg) {
                        if (pledge("stdio rpath proc", NULL) == -1)
                                err(1, "pledge");
                } else {
@@ -284,6 +295,7 @@ main(int argc, char *argv[])
                                err(1, "pledge");
                }
        } else {
+               /* fstat */
                if (pledge("stdio rpath getpw", NULL) == -1)
                        err(1, "pledge");
        }