diff options
Diffstat (limited to 'usr.bin/newgrp/newgrp.c')
| -rw-r--r-- | usr.bin/newgrp/newgrp.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/usr.bin/newgrp/newgrp.c b/usr.bin/newgrp/newgrp.c index f1da1c8cb1f5..0971f4d13b49 100644 --- a/usr.bin/newgrp/newgrp.c +++ b/usr.bin/newgrp/newgrp.c @@ -186,7 +186,7 @@ addgroup(const char *grpname) } } - ngrps_max = sysconf(_SC_NGROUPS_MAX) + 1; + ngrps_max = sysconf(_SC_NGROUPS_MAX); if ((grps = malloc(sizeof(gid_t) * ngrps_max)) == NULL) err(1, "malloc"); if ((ngrps = getgroups(ngrps_max, (gid_t *)grps)) < 0) { @@ -194,7 +194,12 @@ addgroup(const char *grpname) goto end; } - /* Remove requested gid from supp. list if it exists. */ + /* + * Remove requested gid from supp. list if it exists and doesn't match + * our prior egid -- this exception is to avoid providing the user a + * means to get rid of a group that could be used for, e.g., negative + * permissions. + */ if (grp->gr_gid != egid && inarray(grp->gr_gid, grps, ngrps)) { for (i = 0; i < ngrps; i++) if (grps[i] == grp->gr_gid) @@ -217,10 +222,9 @@ addgroup(const char *grpname) goto end; } PRIV_END; - grps[0] = grp->gr_gid; /* Add old effective gid to supp. list if it does not exist. */ - if (egid != grp->gr_gid && !inarray(egid, grps, ngrps)) { + if (!inarray(egid, grps, ngrps)) { if (ngrps == ngrps_max) warnx("too many groups"); else { |