diff options
| author | Todd C. Miller <millert@cvs.openbsd.org> | 2018-09-09 13:53:12 +0000 |
|---|---|---|
| committer | Todd C. Miller <millert@cvs.openbsd.org> | 2018-09-09 13:53:12 +0000 |
| commit | 11fb250ce7e304ccfc265ae5b7852f90e875c491 (patch) | |
| tree | c1a1be489fefd3dc4f301214c22c543c2912c3a3 /usr.bin/rdistd | |
| parent | b2e8c6a3bf408af6f5b18cc9db8476bb6830c0e3 (diff) | |
Fix a crash in rdistd triggered by the recent getpw{ent,nam,uid}
changes. This stems from rdist stashing a pointer to the static
area used by getpw{ent,nam,uid} and using it to avoid repeating
passwd lookups when pw->pw_name matches the user to be looked up.
This relied on undefined behavior, and with the recent passwd
changes, is no longer possible as the old pointer will be invalidated.
A better approach is to use the upcoming uid_from_user(3) functions.
Found by and fix OK tim@
Diffstat (limited to 'usr.bin/rdistd')
| -rw-r--r-- | usr.bin/rdistd/server.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/usr.bin/rdistd/server.c b/usr.bin/rdistd/server.c index e86f764dad8..21f1d4145fb 100644 --- a/usr.bin/rdistd/server.c +++ b/usr.bin/rdistd/server.c @@ -1,4 +1,4 @@ -/* $OpenBSD: server.c,v 1.43 2017/08/30 07:43:52 otto Exp $ */ +/* $OpenBSD: server.c,v 1.44 2018/09/09 13:53:11 millert Exp $ */ /* * Copyright (c) 1983 Regents of the University of California. @@ -188,7 +188,9 @@ fchog(int fd, char *file, char *owner, char *group, int mode) if (userid == 0) { /* running as root; take anything */ if (*owner == ':') { uid = (uid_t) atoi(owner + 1); - } else if (pw == NULL || strcmp(owner, pw->pw_name) != 0) { + } else if (strcmp(owner, locuser) != 0) { + struct passwd *pw; + if ((pw = getpwnam(owner)) == NULL) { if (mode != -1 && IS_ON(mode, S_ISUID)) { message(MT_NOTICE, @@ -203,8 +205,8 @@ fchog(int fd, char *file, char *owner, char *group, int mode) } else uid = pw->pw_uid; } else { - uid = pw->pw_uid; - primegid = pw->pw_gid; + uid = userid; + primegid = groupid; } if (*group == ':') { gid = (gid_t)atoi(group + 1); |