rainlance/amiga-tz
1
0
Fork 0
mirror of https://frontier.innolan.net/rainlance/amiga-tz.git synced 2026-05-09 02:15:17 +00:00
Code Releases Activity

Fix localtime.c undefined behaviors and set errno.

Browse Source 
Christos Zoulas reported a crash due to a tzsetlcl failure to
initialize data in some places, and requested that errno be set
when time functions fail; see:
http://mm.icann.org/pipermail/tz/2014-October/021754.html
While fixing this in a different way, I noticed and fixed another
instance of undefined behavior when read returns a too-small value.
* NEWS: Document this.
* localtime.c (union input_buffer): Rename from u_t.
(union input_buffer, union local_storage):
Move to top level so that two functions can use them.
(tzloadbody): New function, with most of the body of the old tzload.
Check for short reads that leave uninitialized buffers behind.
Define a new constant TZHEADSIZE for this, and use it to simplify
other code that already uses the concept.
(tzload): Use it.  This removes the need for gotos.  Return an errno
value; all callers changed.
(zoneinit): Return bool, not struct state *.  Assume SP is nonnull.
All callers changed.
(zoneinit, tzalloc): Set errno on failure.
(tzsetlcl): Don't crash if zoneinit fails.
* private.h (ENAMETOOLONG): Define if not already defined.
This commit is contained in:
Paul Eggert
2014-10-17 23:51:39 -07:00
parent 8791b19ae9
commit add61671e7
3 changed files with 127 additions and 94 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
NEWS
View File

@@ -35,6 +35,11 @@ Unreleased, experimental changes
Changes affecting code
The time-related library functions now set errno on failure, and
some crashes in the new tzalloc-related library functions have
been fixed. (Thanks to Christos Zoulas for reporting most of
these problems and for suggesting fixes.)
If USG_COMPAT is defined and the requested time stamp is standard time,
the tz library's localtime and mktime functions now set the extern
variable timezone to a value appropriate for that time stamp; and

213
localtime.c
View File

@@ -307,67 +307,64 @@ differ_by_repeat(const time_t t1, const time_t t0)
return t1 - t0 == SECSPERREPEAT;
}
static bool
tzload(register const char *name, register struct state *const sp,
bool doextend)
/* Input buffer for data read from a compiled tz file. */
union input_buffer {
/* The first part of the buffer, interpreted as a header. */
struct tzhead tzhead;
/* The entire buffer. */
char buf[2 * sizeof(struct tzhead) + 2 * sizeof (struct state)
+ 4 * TZ_MAX_TIMES];
};
/* Local storage needed for 'tzloadbody'. */
union local_storage {
/* The file name to be opened. */
char fullname[FILENAME_MAX + 1];
/* The results of analyzing the file's contents after it is opened. */
struct {
/* The input buffer. */
union input_buffer u;
/* A temporary state used for parsing a TZ string in the file. */
struct state st;
} u;
};
/* Load tz data from the file named NAME into *SP. Read extended
format if DOEXTEND. Use *LSP for temporary storage. Return 0 on
success, an errno value on failure. */
static int
tzloadbody(char const *name, struct state *sp, bool doextend,
union local_storage *lsp)
{
register const char * p;
register int i;
register int fid;
register int stored;
register ssize_t nread;
typedef union {
struct tzhead tzhead;
char buf[2 * sizeof(struct tzhead) +
2 * sizeof *sp +
4 * TZ_MAX_TIMES];
} u_t;
union local_storage {
/*
** Section 4.9.1 of the C standard says that
** "FILENAME_MAX expands to an integral constant expression
** that is the size needed for an array of char large enough
** to hold the longest file name string that the implementation
** guarantees can be opened."
*/
char fullname[FILENAME_MAX + 1];
/* The main part of the storage for this function. */
struct {
u_t u;
struct state st;
} u;
};
register char *fullname;
register u_t *up;
register bool doaccess;
register union local_storage *lsp;
#ifdef ALL_STATE
lsp = malloc(sizeof *lsp);
if (!lsp)
return false;
#else /* !defined ALL_STATE */
union local_storage ls;
lsp = &ls;
#endif /* !defined ALL_STATE */
fullname = lsp->fullname;
up = &lsp->u.u;
register char *fullname = lsp->fullname;
register union input_buffer *up = &lsp->u.u;
register int tzheadsize = sizeof (struct tzhead);
sp->goback = sp->goahead = false;
if (! name) {
name = TZDEFAULT;
if (! name)
goto oops;
return EINVAL;
}
if (name[0] == ':')
++name;
doaccess = name[0] == '/';
if (!doaccess) {
p = TZDIR;
if (! p || sizeof lsp->fullname - 1 <= strlen(p) + strlen(name))
goto oops;
char const *p = TZDIR;
if (! p)
return EINVAL;
if (sizeof lsp->fullname - 1 <= strlen(p) + strlen(name))
return ENAMETOOLONG;
strcpy(fullname, p);
strcat(fullname, "/");
strcat(fullname, name);
@@ -377,14 +374,19 @@ tzload(register const char *name, register struct state *const sp,
name = fullname;
}
if (doaccess && access(name, R_OK) != 0)
goto oops;
return errno;
fid = open(name, OPEN_MODE);
if (fid < 0)
goto oops;
return errno;
nread = read(fid, up->buf, sizeof up->buf);
if (close(fid) < 0 || nread <= 0)
goto oops;
if (nread < tzheadsize) {
int err = nread < 0 ? errno : EINVAL;
close(fid);
return err;
}
if (close(fid) < 0)
return errno;
for (stored = 4; stored <= 8; stored *= 2) {
int_fast32_t ttisstdcnt = detzcode(up->tzhead.tzh_ttisstdcnt);
int_fast32_t ttisgmtcnt = detzcode(up->tzhead.tzh_ttisgmtcnt);
@@ -392,16 +394,16 @@ tzload(register const char *name, register struct state *const sp,
int_fast32_t timecnt = detzcode(up->tzhead.tzh_timecnt);
int_fast32_t typecnt = detzcode(up->tzhead.tzh_typecnt);
int_fast32_t charcnt = detzcode(up->tzhead.tzh_charcnt);
p = up->tzhead.tzh_charcnt + sizeof up->tzhead.tzh_charcnt;
char const *p = up->buf + tzheadsize;
if (! (0 <= leapcnt && leapcnt < TZ_MAX_LEAPS
&& 0 < typecnt && typecnt < TZ_MAX_TYPES
&& 0 <= timecnt && timecnt < TZ_MAX_TIMES
&& 0 <= charcnt && charcnt < TZ_MAX_CHARS
&& (ttisstdcnt == typecnt || ttisstdcnt == 0)
&& (ttisgmtcnt == typecnt || ttisgmtcnt == 0)))
goto oops;
return EINVAL;
if (nread
< (p - up->buf /* struct tzhead */
< (tzheadsize /* struct tzhead */
+ timecnt * stored /* ats */
+ timecnt /* types */
+ typecnt * 6 /* ttinfos */
@@ -409,7 +411,7 @@ tzload(register const char *name, register struct state *const sp,
+ leapcnt * (stored + 4) /* lsinfos */
+ ttisstdcnt /* ttisstds */
+ ttisgmtcnt)) /* ttisgmts */
goto oops;
return EINVAL;
sp->leapcnt = leapcnt;
sp->timecnt = timecnt;
sp->typecnt = typecnt;
@@ -429,7 +431,7 @@ tzload(register const char *name, register struct state *const sp,
? time_t_min : at);
if (timecnt && attime <= sp->ats[timecnt - 1]) {
if (attime < sp->ats[timecnt - 1])
goto oops;
return EINVAL;
sp->types[i - 1] = 0;
timecnt--;
}
@@ -442,7 +444,7 @@ tzload(register const char *name, register struct state *const sp,
for (i = 0; i < sp->timecnt; ++i) {
unsigned char typ = *p++;
if (sp->typecnt <= typ)
goto oops;
return EINVAL;
if (sp->types[i])
sp->types[timecnt++] = typ;
}
@@ -456,11 +458,11 @@ tzload(register const char *name, register struct state *const sp,
p += 4;
isdst = *p++;
if (! (isdst < 2))
goto oops;
return EINVAL;
ttisp->tt_isdst = isdst;
abbrind = *p++;
if (! (abbrind < sp->charcnt))
goto oops;
return EINVAL;
ttisp->tt_abbrind = abbrind;
}
for (i = 0; i < sp->charcnt; ++i)
@@ -479,7 +481,7 @@ tzload(register const char *name, register struct state *const sp,
? time_t_min : tr);
if (leapcnt && trans <= sp->lsis[leapcnt - 1].ls_trans) {
if (trans < sp->lsis[leapcnt - 1].ls_trans)
goto oops;
return EINVAL;
leapcnt--;
}
sp->lsis[leapcnt].ls_trans = trans;
@@ -497,7 +499,7 @@ tzload(register const char *name, register struct state *const sp,
ttisp->tt_ttisstd = false;
else {
if (*p != true && *p != false)
goto oops;
return EINVAL;
ttisp->tt_ttisstd = *p++;
}
}
@@ -509,7 +511,7 @@ tzload(register const char *name, register struct state *const sp,
ttisp->tt_ttisgmt = false;
else {
if (*p != true && *p != false)
goto oops;
return EINVAL;
ttisp->tt_ttisgmt = *p++;
}
}
@@ -610,15 +612,27 @@ tzload(register const char *name, register struct state *const sp,
}
}
sp->defaulttype = i;
return 0;
}
/* Load tz data from the file named NAME into *SP. Read extended
format if DOEXTEND. Return 0 on success, an errno value on failure. */
static int
tzload(char const *name, struct state *sp, bool doextend)
{
#ifdef ALL_STATE
free(up);
#endif /* defined ALL_STATE */
return true;
oops:
#ifdef ALL_STATE
free(up);
#endif /* defined ALL_STATE */
return false;
union local_storage *lsp = malloc(sizeof *lsp);
if (!lsp)
return errno;
else {
int err = tzloadbody(name, sp, doextend, lsp);
free(lsp);
return err;
}
#else
union local_storage ls;
return tzloadbody(name, sp, doextend, &ls);
#endif
}
static bool
@@ -970,7 +984,7 @@ tzparse(const char *name, register struct state *const sp,
if (name == NULL)
return false;
}
load_ok = tzload(TZDEFRULES, sp, false);
load_ok = tzload(TZDEFRULES, sp, false) == 0;
if (!load_ok)
sp->leapcnt = 0; /* so, we're off a little */
if (*name != '\0') {
@@ -1165,48 +1179,56 @@ tzparse(const char *name, register struct state *const sp,
static void
gmtload(struct state *const sp)
{
if (! tzload(gmt, sp, true))
if (tzload(gmt, sp, true) != 0)
tzparse(gmt, sp, true);
}
static struct state *
static bool
zoneinit(struct state *sp, char const *name)
{
if (sp) {
if (name && ! name[0]) {
/*
** User wants it fast rather than right.
*/
sp->leapcnt = 0; /* so, we're off a little */
sp->timecnt = 0;
sp->typecnt = 0;
sp->charcnt = 0;
sp->goback = sp->goahead = false;
init_ttinfo(&sp->ttis[0], 0, false, 0);
strcpy(sp->chars, gmt);
sp->defaulttype = 0;
} else if (! (tzload(name, sp, true)
|| (name && name[0] != ':' && tzparse(name, sp, false))))
return NULL;
if (name && ! name[0]) {
/*
** User wants it fast rather than right.
*/
sp->leapcnt = 0; /* so, we're off a little */
sp->timecnt = 0;
sp->typecnt = 0;
sp->charcnt = 0;
sp->goback = sp->goahead = false;
init_ttinfo(&sp->ttis[0], 0, false, 0);
strcpy(sp->chars, gmt);
sp->defaulttype = 0;
return true;
} else {
int err = tzload(name, sp, true);
if (err == 0)
return true;
if (name && name[0] != ':' && tzparse(name, sp, false))
return true;
errno = err;
return false;
}
return sp;
}
static void
tzsetlcl(char const *name)
{
struct state *sp = lclptr;
int lcl = name ? strlen(name) < sizeof lcl_TZname : -1;
if (lcl < 0
? lcl_is_set < 0
: 0 < lcl_is_set && strcmp(lcl_TZname, name) == 0)
return;
if (0 < lcl)
strcpy(lcl_TZname, name);
#ifdef ALL_STATE
if (! lclptr)
lclptr = malloc(sizeof *lclptr);
if (! sp)
lclptr = sp = malloc(sizeof *lclptr);
#endif /* defined ALL_STATE */
zoneinit(lclptr, name);
if (sp) {
if (! zoneinit(sp, name))
zoneinit(sp, "");
if (0 < lcl)
strcpy(lcl_TZname, name);
}
settzname();
lcl_is_set = lcl;
}
@@ -1260,10 +1282,13 @@ timezone_t
tzalloc(char const *name)
{
timezone_t sp = malloc(sizeof *sp);
timezone_t tp = sp ? zoneinit(sp, name) : sp;
if (!tp)
if (sp && ! zoneinit(sp, name)) {
int err = errno;
free(sp);
return tp;
errno = err;
return NULL;
}
return sp;
}
void

3
private.h
View File

@@ -107,6 +107,9 @@
#include "errno.h"
#ifndef ENAMETOOLONG
# define ENAMETOOLONG EINVAL
#endif
#ifndef EOVERFLOW
# define EOVERFLOW EINVAL
#endif