diff options
| -rw-r--r-- | io/Makefile | 1 | ||||
| -rw-r--r-- | io/ftw.c | 39 | ||||
| -rw-r--r-- | io/tst-ftw-bz28126.c | 97 |
3 files changed, 117 insertions, 20 deletions
diff --git a/io/Makefile b/io/Makefile index 9871ecb..ecf65ab 100644 --- a/io/Makefile +++ b/io/Makefile @@ -79,6 +79,7 @@ tests := test-utime test-stat test-stat2 test-lfs tst-getcwd \ tst-futimens \ tst-utimensat \ tst-closefrom \ + tst-ftw-bz28126 tests-time64 := \ tst-futimens-time64 \ @@ -203,6 +203,20 @@ struct ftw_data void *known_objects; }; +static bool +ftw_allocate (struct ftw_data *data, size_t newsize) +{ + void *newp = realloc (data->dirstreams, data->maxdir + * sizeof (struct dir_data *) + + newsize); + if (newp == NULL) + return false; + data->dirstreams = newp; + data->dirbufsize = newsize; + data->dirbuf = (char *) data->dirstreams + + data->maxdir * sizeof (struct dir_data *); + return true; +} /* Internally we use the FTW_* constants used for `nftw'. When invoked as `ftw', map each flag to the subset of values used by `ftw'. */ @@ -388,17 +402,9 @@ process_entry (struct ftw_data *data, struct dir_data *dir, const char *name, return 0; new_buflen = data->ftw.base + namlen + 2; - if (data->dirbufsize < new_buflen) - { - /* Enlarge the buffer. */ - char *newp; - - data->dirbufsize = 2 * new_buflen; - newp = (char *) realloc (data->dirbuf, data->dirbufsize); - if (newp == NULL) - return -1; - data->dirbuf = newp; - } + if (data->dirbufsize < new_buflen + && !ftw_allocate (data, 2 * new_buflen)) + return -1; *((char *) __mempcpy (data->dirbuf + data->ftw.base, name, namlen)) = '\0'; @@ -628,7 +634,7 @@ __attribute ((noinline)) ftw_startup (const char *dir, int is_nftw, void *func, int descriptors, int flags) { - struct ftw_data data; + struct ftw_data data = { .dirstreams = NULL }; struct STRUCT_STAT st; int result = 0; int save_err; @@ -646,16 +652,9 @@ ftw_startup (const char *dir, int is_nftw, void *func, int descriptors, data.maxdir = descriptors < 1 ? 1 : descriptors; data.actdir = 0; /* PATH_MAX is always defined when we get here. */ - data.dirbufsize = MAX (2 * strlen (dir), PATH_MAX); - data.dirstreams = malloc (data.maxdir * sizeof (struct dir_data *) - + data.dirbufsize); - if (data.dirstreams == NULL) + if (!ftw_allocate (&data, MAX (2 * strlen (dir), PATH_MAX))) return -1; - memset (data.dirstreams, '\0', data.maxdir * sizeof (struct dir_data *)); - - data.dirbuf = (char *) data.dirstreams - + data.maxdir * sizeof (struct dir_data *); cp = __stpcpy (data.dirbuf, dir); /* Strip trailing slashes. */ while (cp > data.dirbuf + 1 && cp[-1] == '/') diff --git a/io/tst-ftw-bz28126.c b/io/tst-ftw-bz28126.c new file mode 100644 index 0000000..94044ab --- /dev/null +++ b/io/tst-ftw-bz28126.c @@ -0,0 +1,97 @@ +/* Check if internal buffer reallocation work for large paths (BZ #28126) + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#include <errno.h> +#include <ftw.h> +#include <limits.h> +#include <string.h> +#include <stdlib.h> +#include <support/check.h> +#include <support/support.h> +#include <support/temp_file.h> +#include <support/xunistd.h> +#include <stdio.h> + +static int +my_func (const char *file, const struct stat *sb, int flag) +{ + return 0; +} + +static const char folder[NAME_MAX] = { [0 ... 253] = 'a', [254] = '\0' }; + +#define NSUBFOLDERS 16 +static int nsubfolders; + +static void +do_cleanup (void) +{ + xchdir (".."); + for (int i = 0; i < nsubfolders; i++) + { + remove (folder); + xchdir (".."); + } + remove (folder); +} +#define CLEANUP_HANDLER do_cleanup + +static void +check_mkdir (const char *path) +{ + int r = mkdir (path, 0777); + /* Some filesystem such as overlayfs does not support larger path required + to trigger the internal buffer reallocation. */ + if (r != 0) + { + if (errno == ENAMETOOLONG) + FAIL_UNSUPPORTED ("the filesystem does not support the required" + "large path"); + else + FAIL_EXIT1 ("mkdir (\"%s\", 0%o): %m", folder, 0777); + } +} + +static int +do_test (void) +{ + char *tempdir = support_create_temp_directory ("tst-bz28126"); + + /* Create path with various subfolders to force an internal buffer + reallocation within ntfw. */ + char *path = xasprintf ("%s/%s", tempdir, folder); + check_mkdir (path); + xchdir (path); + free (path); + for (int i = 0; i < NSUBFOLDERS - 1; i++) + { + check_mkdir (folder); + xchdir (folder); + nsubfolders++; + } + + TEST_COMPARE (ftw (tempdir, my_func, 20), 0); + + free (tempdir); + + do_cleanup (); + + return 0; +} + +#include <support/test-driver.c> |