diff options
| author | Paul Eggert <eggert@cs.ucla.edu> | 2007-02-03 18:45:46 +0100 |
|---|---|---|
| committer | Jim Meyering <jim@meyering.net> | 2007-02-03 18:45:46 +0100 |
| commit | b28a8851ed22dbf0cd123974a0c97ae0b82bec2b (patch) | |
| tree | 2ee82ce576b7026f2b99268044e627daf203fb81 /src | |
| parent | 1c73876f5f7973ca41caaf0ce326254b1081713a (diff) | |
| download | coreutils-b28a8851ed22dbf0cd123974a0c97ae0b82bec2b.tar.xz | |
* NEWS: Document fix for cp --preserve=mode.
* src/copy.c (copy_internal): Omit the group- or other-writeable
permissions when creating a directory, to avoid a race condition
if the special mode bits aren't right just after the directory is
created.
* src/cp.c (make_dir_parents_private): Likewise.
* tests/cp/parent-perm-race: Test for the "cp --preserve=mode"
race fix in copy.c.
Diffstat (limited to 'src')
| -rw-r--r-- | src/copy.c | 23 | ||||
| -rw-r--r-- | src/cp.c | 12 |
2 files changed, 22 insertions, 13 deletions
diff --git a/src/copy.c b/src/copy.c index d9ad254a9..5ec5a921c 100644 --- a/src/copy.c +++ b/src/copy.c @@ -1,5 +1,5 @@ /* copy.c -- core functions for copying files and directories - Copyright (C) 89, 90, 91, 1995-2006 Free Software Foundation. + Copyright (C) 89, 90, 91, 1995-2007 Free Software Foundation. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -1005,6 +1005,7 @@ copy_internal (char const *src_name, char const *dst_name, struct stat dst_sb; mode_t src_mode; mode_t dst_mode IF_LINT (= 0); + mode_t dst_mode_bits; mode_t omitted_permissions; bool restore_dst_mode = false; char *earlier_file = NULL; @@ -1504,13 +1505,16 @@ copy_internal (char const *src_name, char const *dst_name, new_dst = true; } - /* If the ownership might change, omit some permissions at first, so - unauthorized users cannot nip in before the file has the right - ownership. */ + /* If the ownership might change, or if it is a directory (whose + special mode bits may change after the directory is created), + omit some permissions at first, so unauthorized users cannot nip + in before the file is ready. */ + dst_mode_bits = (x->set_mode ? x->mode : src_mode) & CHMOD_MODE_BITS; omitted_permissions = - (x->preserve_ownership - ? (x->set_mode ? x->mode : src_mode) & (S_IRWXG | S_IRWXO) - : 0); + (dst_mode_bits + & (x->preserve_ownership ? S_IRWXG | S_IRWXO + : S_ISDIR (src_mode) ? S_IWGRP | S_IWOTH + : 0)); delayed_ok = true; @@ -1549,10 +1553,7 @@ copy_internal (char const *src_name, char const *dst_name, (src_mode & ~S_IRWXUGO) != 0. However, common practice is to ask mkdir to copy all the CHMOD_MODE_BITS, letting mkdir decide what to do with S_ISUID | S_ISGID | S_ISVTX. */ - mode_t mkdir_mode = - ((x->set_mode ? x->mode : src_mode) - & CHMOD_MODE_BITS & ~omitted_permissions); - if (mkdir (dst_name, mkdir_mode) != 0) + if (mkdir (dst_name, dst_mode_bits & ~omitted_permissions) != 0) { error (0, errno, _("cannot create directory %s"), quote (dst_name)); @@ -435,8 +435,16 @@ make_dir_parents_private (char const *const_dir, size_t src_offset, return false; } src_mode = stats.st_mode; - omitted_permissions = - x->preserve_ownership ? src_mode & (S_IRWXG | S_IRWXO) : 0; + + /* If the ownership or special mode bits might change, + omit some permissions at first, so unauthorized users + cannot nip in before the file is ready. */ + omitted_permissions = (src_mode + & (x->preserve_ownership + ? S_IRWXG | S_IRWXO + : x->preserve_mode + ? S_IWGRP | S_IWOTH + : 0)); /* POSIX says mkdir's behavior is implementation-defined when (src_mode & ~S_IRWXUGO) != 0. However, common practice is |