ping
On Sat, Jan 28, 2017 at 03:25:53PM +0100, Theo Buehler wrote:
> The problem:
>
> $ mount /dev/tty /tmp
> Abort trap (core dumped)
>
> The relevant kdump snippet:
>
> 45441 mount CALL open(0x7f7ffffeb580,0x10000<O_RDONLY|O_CLOEXEC>)
> 45441 mount NAMI "/dev/tty"
> 45441 mount RET open 3
> 45441 mount CALL ioctl(3,DIOCGDINFO,0x7f7ffffeb350)
> 45441 mount PLDG ioctl, "tty", errno 1 Operation not permitted
> 45441 mount PSIG SIGABRT SIG_DFL
>
> and the backtrace:
>
> #0 0x00001103967a72aa in ioctl () at <stdin>:2
> #1 0x0000110364ca97b9 in readlabelfs (device=0x7f7ffffd0ada "/dev/tty",
> verbose=0) at /usr/src/lib/libutil/readlabel.c:128
> #2 0x00001100d4201210 in main () from /usr/obj/sbin/mount/mount
>
> As usual, the fix consists of hoisting the problematic bit above the
> pledge call. This has the side effect that the string bashing functions
> hasopt(), catopt() and maketypelist() are now called without pledge from
> the getopt switch, but I don't think that's a problem. It would be easy
> to postpone the call to maketypelist() until after pledge, if anyone is
> worried about it.
>
> Index: mount.c
> ===================================================================
> RCS file: /var/cvs/src/sbin/mount/mount.c,v
> retrieving revision 1.70
> diff -u -p -r1.70 mount.c
> --- mount.c 25 Jan 2017 02:33:25 -0000 1.70
> +++ mount.c 28 Jan 2017 14:11:28 -0000
> @@ -109,9 +109,6 @@ main(int argc, char * const argv[])
> int all, ch, forceall, i, mntsize, rval, new;
> char *options, mntpath[PATH_MAX];
>
> - if (pledge("stdio rpath disklabel proc exec", NULL) == -1)
> - err(1, "pledge");
> -
> all = forceall = 0;
> options = NULL;
> vfstype = "ffs";
> @@ -168,6 +165,25 @@ main(int argc, char * const argv[])
> argc -= optind;
> argv += optind;
>
> + if (typelist == NULL && argc == 2) {
> + /*
> + * If -t flag has not been specified, and spec contains either
> + * a ':' or a '@' then assume that an NFS filesystem is being
> + * specified ala Sun. If not, check the disklabel for a
> + * known filesystem type.
> + */
> + if (strpbrk(argv[0], ":@") != NULL)
> + vfstype = "nfs";
> + else {
> + char *labelfs = readlabelfs(argv[0], 0);
> + if (labelfs != NULL)
> + vfstype = labelfs;
> + }
> + }
> +
> + if (pledge("stdio rpath disklabel proc exec", NULL) == -1)
> + err(1, "pledge");
> +
> #define BADTYPE(type)
> \
> (strcmp(type, FSTAB_RO) && \
> strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
> @@ -261,23 +277,7 @@ main(int argc, char * const argv[])
> mntonname, options, fs->fs_mntops, skip);
> break;
> case 2:
> - /*
> - * If -t flag has not been specified, and spec contains either
> - * a ':' or a '@' then assume that an NFS filesystem is being
> - * specified ala Sun. If not, check the disklabel for a
> - * known filesystem type.
> - */
> - if (typelist == NULL) {
> - if (strpbrk(argv[0], ":@") != NULL)
> - vfstype = "nfs";
> - else {
> - char *labelfs = readlabelfs(argv[0], 0);
> - if (labelfs != NULL)
> - vfstype = labelfs;
> - }
> - }
> - rval = mountfs(vfstype,
> - argv[0], argv[1], options, NULL, 0);
> + rval = mountfs(vfstype, argv[0], argv[1], options, NULL, 0);
> break;
> default:
> usage();
>
