diff options
Diffstat (limited to 'time/tzfile.c')
| -rw-r--r-- | time/tzfile.c | 42 |
1 files changed, 33 insertions, 9 deletions
diff --git a/time/tzfile.c b/time/tzfile.c index d80789d..761ddc9 100644 --- a/time/tzfile.c +++ b/time/tzfile.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1991, 92, 93, 95, 96 Free Software Foundation, Inc. +/* Copyright (C) 1991, 92, 93, 95, 96, 97 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 @@ -113,16 +113,28 @@ __tzfile_read (const char *file) if (*file != '/') { - static const char tzdir[] = TZDIR; - register const unsigned int len = strlen (file) + 1; - char *new = (char *) __alloca (sizeof (tzdir) + len); - memcpy (new, tzdir, sizeof(tzdir) - 1); - new[sizeof (tzdir) - 1] = '/'; - memcpy (&new[sizeof (tzdir)], file, len); + static const char default_tzdir[] = TZDIR; + const char *tzdir; + unsigned int len, tzdir_len; + char *new; + + tzdir = __secure_getenv ("TZDIR"); + if (tzdir == NULL || *tzdir == '\0') + { + tzdir = default_tzdir; + tzdir_len = sizeof (default_tzdir) - 1; + } + else + tzdir_len = strlen (tzdir); + len = strlen (file) + 1; + new = (char *) __alloca (tzdir_len + 1 + len); + memcpy (new, tzdir, tzdir_len); + new[tzdir_len] = '/'; + memcpy (&new[tzdir_len + 1], file, len); file = new; } - f = fopen(file, "r"); + f = fopen (file, "r"); if (f == NULL) return; @@ -171,6 +183,12 @@ __tzfile_read (const char *file) fread(type_idxs, 1, num_transitions, f) != num_transitions) goto lose; + /* Check for bogus indices in the data file, so we can hereafter + safely use type_idxs[T] as indices into `types' and never crash. */ + for (i = 0; i < num_transitions; ++i) + if (type_idxs[i] >= num_types) + goto lose; + if (BYTE_ORDER != BIG_ENDIAN || sizeof (time_t) != 4) { /* Decode the transition times, stored as 4-byte integers in @@ -189,6 +207,8 @@ __tzfile_read (const char *file) fread (&types[i].isdst, 1, 1, f) != 1 || fread (&types[i].idx, 1, 1, f) != 1) goto lose; + if (types[i].idx >= chars) /* Bogus index in data file. */ + goto lose; types[i].offset = (long int) decode (x); } @@ -335,6 +355,10 @@ __tzfile_default (char *std, char *dst, long int stdoff, long int dstoff) types[1].offset = dstoff; types[1].isdst = 1; + /* Reset the zone names to point to the user's names. */ + __tzname[0] = &zone_names[0]; + __tzname[1] = &zone_names[stdlen]; + compute_tzname_max (stdlen + dstlen); } @@ -425,7 +449,7 @@ compute_tzname_max (size_t chars) const char *start = p; while (*p != '\0') ++p; - if (p - start > __tzname_cur_max) + if ((size_t) (p - start) > __tzname_cur_max) __tzname_cur_max = p - start; } while (++p < &zone_names[chars]); } |