d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
8688532f07
freebsd-dev/bin/ls/print.c
Kirk McKusick 927f8d8bbb Handle NULL return from localtime(3) in ls(1) and find(1) 
The ls(1) (with -l option) and find(1) (with -ls option) utilties
segment fault when operating on files with very large modification
times. A recent disk corruption set a spurious bit in the mtime
field of one of my files to 0x8000000630b0167 (576460753965089127)
which is in year 18,266,940,962. I discovered the problem when
running fsck_ffs(8) which uses ctime(3) to convert it to a readable
format. Ctime cannot fit the year into its four character field, so
returns ??? ??? ?? ??:??:?? ???? (typically Thu Nov 24 18:22:48 2021).

With the filesystem mounted, I used `ls -l' to see how it would
report the modification time and it segment faulted. The find(1)
program also segment faulted (see script below). Both these utilities
call the localtime(3) function to decode the modification time.
Localtime(3) returns a pointer to a struct tm (which breaks things
out into its component pieces: year, month, day, hour, minute,
second). The ls(1) and find(1) utilities then print out the date
based on the appropriate fields in the returned tm structure.

Although not documented in the localtime(3) manual page, localtime(3)
returns a NULL pointer if the passed in time translates to a year
that will not fit in an "int" (which if "int" is 32-bits cannot
hold the year 18,266,940,962). Since ls(1) and find(1) do not check
for a NULL struct tm * return from localtime(3), they segment fault
when they try to dereference it.

When localtime(3) returns NULL, the attached patches produce a date
string of "bad date val". This string is chosen because it has the
same number of characters (12) and white spaces (2) as the usual
date string, for example "Sep 3 22:06" or "May 15 2017".

The most recent ANSI standard for localtime(3) does say that localtime(3)
can return NULL (see https://pubs.opengroup.org/onlinepubs/9699919799/
and enter localtime in the search box). Our localtime(3) man page should
be updated to indicate that NULL is a possible return. More importantly,
there are over 100 uses of localtime(3) in the FreeBSD source tree (see
Differential Revision D36474 for the list). Most do not check for a NULL
return from localtime(3).

Reported by:  Peter Holm
Reviewed by:  kib, Chuck Silvers, Warner Losh
MFC after:    2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D36474
2022-09-09 14:30:42 -07:00

840 lines
18 KiB
C
Raw Blame History

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1989, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Michael Fischbein.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static char sccsid[] = "@(#)print.c 8.4 (Berkeley) 4/17/94";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/acl.h>
#include <err.h>
#include <errno.h>
#include <fts.h>
#include <langinfo.h>
#include <libutil.h>
#include <limits.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <wchar.h>
#ifdef COLORLS
#include <ctype.h>
#include <termcap.h>
#include <signal.h>
#endif
#include "ls.h"
#include "extern.h"
static int printaname(const FTSENT *, u_long, u_long);
static void printdev(size_t, dev_t);
static void printlink(const FTSENT *);
static void printtime(time_t);
static int printtype(u_int);
static void printsize(size_t, off_t);
#ifdef COLORLS
static void endcolor_termcap(int);
static void endcolor_ansi(void);
static void endcolor(int);
static int colortype(mode_t);
#endif
static void aclmode(char *, const FTSENT *);
#define IS_NOPRINT(p) ((p)->fts_number == NO_PRINT)
#ifdef COLORLS
/* Most of these are taken from <sys/stat.h> */
typedef enum Colors {
C_DIR, /* directory */
C_LNK, /* symbolic link */
C_SOCK, /* socket */
C_FIFO, /* pipe */
C_EXEC, /* executable */
C_BLK, /* block special */
C_CHR, /* character special */
C_SUID, /* setuid executable */
C_SGID, /* setgid executable */
C_WSDIR, /* directory writeble to others, with sticky
* bit */
C_WDIR, /* directory writeble to others, without
* sticky bit */
C_NUMCOLORS /* just a place-holder */
} Colors;
static const char *defcolors = "exfxcxdxbxegedabagacad";
/* colors for file types */
static struct {
int num[2];
bool bold;
bool underline;
} colors[C_NUMCOLORS];
#endif
static size_t padding_for_month[12];
static size_t month_max_size = 0;
void
printscol(const DISPLAY *dp)
{
FTSENT *p;
for (p = dp->list; p; p = p->fts_link) {
if (IS_NOPRINT(p))
continue;
(void)printaname(p, dp->s_inode, dp->s_block);
(void)putchar('\n');
}
}
/*
* print name in current style
*/
int
printname(const char *name)
{
if (f_octal || f_octal_escape)
return prn_octal(name);
else if (f_nonprint)
return prn_printable(name);
else
return prn_normal(name);
}
static const char *
get_abmon(int mon)
{
switch (mon) {
case 0: return (nl_langinfo(ABMON_1));
case 1: return (nl_langinfo(ABMON_2));
case 2: return (nl_langinfo(ABMON_3));
case 3: return (nl_langinfo(ABMON_4));
case 4: return (nl_langinfo(ABMON_5));
case 5: return (nl_langinfo(ABMON_6));
case 6: return (nl_langinfo(ABMON_7));
case 7: return (nl_langinfo(ABMON_8));
case 8: return (nl_langinfo(ABMON_9));
case 9: return (nl_langinfo(ABMON_10));
case 10: return (nl_langinfo(ABMON_11));
case 11: return (nl_langinfo(ABMON_12));
}
/* should never happen */
abort();
}
static size_t
mbswidth(const char *month)
{
wchar_t wc;
size_t width, donelen, clen, w;
width = donelen = 0;
while ((clen = mbrtowc(&wc, month + donelen, MB_LEN_MAX, NULL)) != 0) {
if (clen == (size_t)-1 || clen == (size_t)-2)
return (-1);
donelen += clen;
if ((w = wcwidth(wc)) == (size_t)-1)
return (-1);
width += w;
}
return (width);
}
static void
compute_abbreviated_month_size(void)
{
int i;
size_t width;
size_t months_width[12];
for (i = 0; i < 12; i++) {
width = mbswidth(get_abmon(i));
if (width == (size_t)-1) {
month_max_size = -1;
return;
}
months_width[i] = width;
if (width > month_max_size)
month_max_size = width;
}
for (i = 0; i < 12; i++)
padding_for_month[i] = month_max_size - months_width[i];
}
void
printlong(const DISPLAY *dp)
{
struct stat *sp;
FTSENT *p;
NAMES *np;
char buf[20];
#ifdef COLORLS
int color_printed = 0;
#endif
if ((dp->list == NULL || dp->list->fts_level != FTS_ROOTLEVEL) &&
(f_longform || f_size)) {
(void)printf("total %lu\n", howmany(dp->btotal, blocksize));
}
for (p = dp->list; p; p = p->fts_link) {
if (IS_NOPRINT(p))
continue;
sp = p->fts_statp;
if (f_inode)
(void)printf("%*ju ",
dp->s_inode, (uintmax_t)sp->st_ino);
if (f_size)
(void)printf("%*jd ",
dp->s_block, howmany(sp->st_blocks, blocksize));
strmode(sp->st_mode, buf);
aclmode(buf, p);
np = p->fts_pointer;
(void)printf("%s %*ju %-*s %-*s ", buf, dp->s_nlink,
(uintmax_t)sp->st_nlink, dp->s_user, np->user, dp->s_group,
np->group);
if (f_flags)
(void)printf("%-*s ", dp->s_flags, np->flags);
if (f_label)
(void)printf("%-*s ", dp->s_label, np->label);
if (S_ISCHR(sp->st_mode) || S_ISBLK(sp->st_mode))
printdev(dp->s_size, sp->st_rdev);
else
printsize(dp->s_size, sp->st_size);
if (f_accesstime)
printtime(sp->st_atime);
else if (f_birthtime)
printtime(sp->st_birthtime);
else if (f_statustime)
printtime(sp->st_ctime);
else
printtime(sp->st_mtime);
#ifdef COLORLS
if (f_color)
color_printed = colortype(sp->st_mode);
#endif
(void)printname(p->fts_name);
#ifdef COLORLS
if (f_color && color_printed)
endcolor(0);
#endif
if (f_type)
(void)printtype(sp->st_mode);
if (S_ISLNK(sp->st_mode))
printlink(p);
(void)putchar('\n');
}
}
void
printstream(const DISPLAY *dp)
{
FTSENT *p;
int chcnt;
for (p = dp->list, chcnt = 0; p; p = p->fts_link) {
if (p->fts_number == NO_PRINT)
continue;
/* XXX strlen does not take octal escapes into account. */
if (strlen(p->fts_name) + chcnt +
(p->fts_link ? 2 : 0) >= (unsigned)termwidth) {
putchar('\n');
chcnt = 0;
}
chcnt += printaname(p, dp->s_inode, dp->s_block);
if (p->fts_link) {
printf(", ");
chcnt += 2;
}
}
if (chcnt)
putchar('\n');
}
void
printcol(const DISPLAY *dp)
{
static FTSENT **array;
static int lastentries = -1;
FTSENT *p;
FTSENT **narray;
int base;
int chcnt;
int cnt;
int col;
int colwidth;
int endcol;
int num;
int numcols;
int numrows;
int row;
int tabwidth;
if (f_notabs)
tabwidth = 1;
else
tabwidth = 8;
/*
* Have to do random access in the linked list -- build a table
* of pointers.
*/
if (dp->entries > lastentries) {
if ((narray =
realloc(array, dp->entries * sizeof(FTSENT *))) == NULL) {
warn(NULL);
printscol(dp);
return;
}
lastentries = dp->entries;
array = narray;
}
for (p = dp->list, num = 0; p; p = p->fts_link)
if (p->fts_number != NO_PRINT)
array[num++] = p;
colwidth = dp->maxlen;
if (f_inode)
colwidth += dp->s_inode + 1;
if (f_size)
colwidth += dp->s_block + 1;
if (f_type)
colwidth += 1;
colwidth = (colwidth + tabwidth) & ~(tabwidth - 1);
if (termwidth < 2 * colwidth) {
printscol(dp);
return;
}
numcols = termwidth / colwidth;
numrows = num / numcols;
if (num % numcols)
++numrows;
if ((dp->list == NULL || dp->list->fts_level != FTS_ROOTLEVEL) &&
(f_longform || f_size)) {
(void)printf("total %lu\n", howmany(dp->btotal, blocksize));
}
base = 0;
for (row = 0; row < numrows; ++row) {
endcol = colwidth;
if (!f_sortacross)
base = row;
for (col = 0, chcnt = 0; col < numcols; ++col) {
chcnt += printaname(array[base], dp->s_inode,
dp->s_block);
if (f_sortacross)
base++;
else
base += numrows;
if (base >= num)
break;
while ((cnt = ((chcnt + tabwidth) & ~(tabwidth - 1)))
<= endcol) {
if (f_sortacross && col + 1 >= numcols)
break;
(void)putchar(f_notabs ? ' ' : '\t');
chcnt = cnt;
}
endcol += colwidth;
}
(void)putchar('\n');
}
}
/*
* print [inode] [size] name
* return # of characters printed, no trailing characters.
*/
static int
printaname(const FTSENT *p, u_long inodefield, u_long sizefield)
{
struct stat *sp;
int chcnt;
#ifdef COLORLS
int color_printed = 0;
#endif
sp = p->fts_statp;
chcnt = 0;
if (f_inode)
chcnt += printf("%*ju ",
(int)inodefield, (uintmax_t)sp->st_ino);
if (f_size)
chcnt += printf("%*jd ",
(int)sizefield, howmany(sp->st_blocks, blocksize));
#ifdef COLORLS
if (f_color)
color_printed = colortype(sp->st_mode);
#endif
chcnt += printname(p->fts_name);
#ifdef COLORLS
if (f_color && color_printed)
endcolor(0);
#endif
if (f_type)
chcnt += printtype(sp->st_mode);
return (chcnt);
}
/*
* Print device special file major and minor numbers.
*/
static void
printdev(size_t width, dev_t dev)
{
(void)printf("%#*jx ", (u_int)width, (uintmax_t)dev);
}
static void
ls_strftime(char *str, size_t len, const char *fmt, const struct tm *tm)
{
char *posb, nfmt[BUFSIZ];
const char *format = fmt;
if ((posb = strstr(fmt, "%b")) != NULL) {
if (month_max_size == 0) {
compute_abbreviated_month_size();
}
if (month_max_size > 0 && tm != NULL) {
snprintf(nfmt, sizeof(nfmt), "%.*s%s%*s%s",
(int)(posb - fmt), fmt,
get_abmon(tm->tm_mon),
(int)padding_for_month[tm->tm_mon],
"",
posb + 2);
format = nfmt;
}
}
if (tm != NULL)
strftime(str, len, format, tm);
else
strlcpy(str, "bad date val", len);
}
static void
printtime(time_t ftime)
{
char longstring[80];
static time_t now = 0;
const char *format;
static int d_first = -1;
if (d_first < 0)
d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
if (now == 0)
now = time(NULL);
#define SIXMONTHS ((365 / 2) * 86400)
if (f_timeformat) /* user specified format */
format = f_timeformat;
else if (f_sectime)
/* mmm dd hh:mm:ss yyyy || dd mmm hh:mm:ss yyyy */
format = d_first ? "%e %b %T %Y" : "%b %e %T %Y";
else if (ftime + SIXMONTHS > now && ftime < now + SIXMONTHS)
/* mmm dd hh:mm || dd mmm hh:mm */
format = d_first ? "%e %b %R" : "%b %e %R";
else
/* mmm dd yyyy || dd mmm yyyy */
format = d_first ? "%e %b %Y" : "%b %e %Y";
ls_strftime(longstring, sizeof(longstring), format, localtime(&ftime));
fputs(longstring, stdout);
fputc(' ', stdout);
}
static int
printtype(u_int mode)
{
if (f_slash) {
if ((mode & S_IFMT) == S_IFDIR) {
(void)putchar('/');
return (1);
}
return (0);
}
switch (mode & S_IFMT) {
case S_IFDIR:
(void)putchar('/');
return (1);
case S_IFIFO:
(void)putchar('|');
return (1);
case S_IFLNK:
(void)putchar('@');
return (1);
case S_IFSOCK:
(void)putchar('=');
return (1);
case S_IFWHT:
(void)putchar('%');
return (1);
default:
break;
}
if (mode & (S_IXUSR | S_IXGRP | S_IXOTH)) {
(void)putchar('*');
return (1);
}
return (0);
}
#ifdef COLORLS
static int
putch(int c)
{
(void)putchar(c);
return 0;
}
static int
writech(int c)
{
char tmp = (char)c;
(void)write(STDOUT_FILENO, &tmp, 1);
return 0;
}
static void
printcolor_termcap(Colors c)
{
char *ansiseq;
if (colors[c].bold)
tputs(enter_bold, 1, putch);
if (colors[c].underline)
tputs(enter_underline, 1, putch);
if (colors[c].num[0] != -1) {
ansiseq = tgoto(ansi_fgcol, 0, colors[c].num[0]);
if (ansiseq)
tputs(ansiseq, 1, putch);
}
if (colors[c].num[1] != -1) {
ansiseq = tgoto(ansi_bgcol, 0, colors[c].num[1]);
if (ansiseq)
tputs(ansiseq, 1, putch);
}
}
static void
printcolor_ansi(Colors c)
{
printf("\033[");
if (colors[c].bold)
printf("1");
if (colors[c].underline)
printf(";4");
if (colors[c].num[0] != -1)
printf(";3%d", colors[c].num[0]);
if (colors[c].num[1] != -1)
printf(";4%d", colors[c].num[1]);
printf("m");
}
static void
printcolor(Colors c)
{
if (explicitansi)
printcolor_ansi(c);
else
printcolor_termcap(c);
}
static void
endcolor_termcap(int sig)
{
tputs(ansi_coloff, 1, sig ? writech : putch);
tputs(attrs_off, 1, sig ? writech : putch);
}
static void
endcolor_ansi(void)
{
printf("\33[m");
}
static void
endcolor(int sig)
{
if (explicitansi)
endcolor_ansi();
else
endcolor_termcap(sig);
}
static int
colortype(mode_t mode)
{
switch (mode & S_IFMT) {
case S_IFDIR:
if (mode & S_IWOTH)
if (mode & S_ISTXT)
printcolor(C_WSDIR);
else
printcolor(C_WDIR);
else
printcolor(C_DIR);
return (1);
case S_IFLNK:
printcolor(C_LNK);
return (1);
case S_IFSOCK:
printcolor(C_SOCK);
return (1);
case S_IFIFO:
printcolor(C_FIFO);
return (1);
case S_IFBLK:
printcolor(C_BLK);
return (1);
case S_IFCHR:
printcolor(C_CHR);
return (1);
default:;
}
if (mode & (S_IXUSR | S_IXGRP | S_IXOTH)) {
if (mode & S_ISUID)
printcolor(C_SUID);
else if (mode & S_ISGID)
printcolor(C_SGID);
else
printcolor(C_EXEC);
return (1);
}
return (0);
}
void
parsecolors(const char *cs)
{
int i;
int j;
size_t len;
char c[2];
short legacy_warn = 0;
if (cs == NULL)
cs = ""; /* LSCOLORS not set */
len = strlen(cs);
for (i = 0; i < (int)C_NUMCOLORS; i++) {
colors[i].bold = false;
colors[i].underline = false;
if (len <= 2 * (size_t)i) {
c[0] = defcolors[2 * i];
c[1] = defcolors[2 * i + 1];
} else {
c[0] = cs[2 * i];
c[1] = cs[2 * i + 1];
}
for (j = 0; j < 2; j++) {
/* Legacy colours used 0-7 */
if (c[j] >= '0' && c[j] <= '7') {
colors[i].num[j] = c[j] - '0';
if (!legacy_warn) {
warnx("LSCOLORS should use "
"characters a-h instead of 0-9 ("
"see the manual page)");
}
legacy_warn = 1;
} else if (c[j] >= 'a' && c[j] <= 'h')
colors[i].num[j] = c[j] - 'a';
else if (c[j] >= 'A' && c[j] <= 'H') {
colors[i].num[j] = c[j] - 'A';
if (j == 1)
colors[i].underline = true;
else
colors[i].bold = true;
} else if (tolower((unsigned char)c[j]) == 'x') {
if (j == 1 && c[j] == 'X')
colors[i].underline = true;
colors[i].num[j] = -1;
} else {
warnx("invalid character '%c' in LSCOLORS"
" env var", c[j]);
colors[i].num[j] = -1;
}
}
}
}
void
colorquit(int sig)
{
endcolor(sig);
(void)signal(sig, SIG_DFL);
(void)kill(getpid(), sig);
}
#endif /* COLORLS */
static void
printlink(const FTSENT *p)
{
int lnklen;
char name[MAXPATHLEN + 1];
char path[MAXPATHLEN + 1];
if (p->fts_level == FTS_ROOTLEVEL)
(void)snprintf(name, sizeof(name), "%s", p->fts_name);
else
(void)snprintf(name, sizeof(name),
"%s/%s", p->fts_parent->fts_accpath, p->fts_name);
if ((lnklen = readlink(name, path, sizeof(path) - 1)) == -1) {
(void)fprintf(stderr, "\nls: %s: %s\n", name, strerror(errno));
return;
}
path[lnklen] = '\0';
(void)printf(" -> ");
(void)printname(path);
}
static void
printsize(size_t width, off_t bytes)
{
if (f_humanval) {
/*
* Reserve one space before the size and allocate room for
* the trailing '\0'.
*/
char buf[HUMANVALSTR_LEN - 1 + 1];
humanize_number(buf, sizeof(buf), (int64_t)bytes, "",
HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
(void)printf("%*s ", (u_int)width, buf);
} else if (f_thousands) { /* with commas */
/* This format assignment needed to work round gcc bug. */
const char *format = "%*j'd ";
(void)printf(format, (u_int)width, bytes);
} else
(void)printf("%*jd ", (u_int)width, bytes);
}
/*
* Add a + after the standard rwxrwxrwx mode if the file has an
* ACL. strmode() reserves space at the end of the string.
*/
static void
aclmode(char *buf, const FTSENT *p)
{
char name[MAXPATHLEN + 1];
int ret, trivial;
static dev_t previous_dev = NODEV;
static int supports_acls = -1;
static int type = ACL_TYPE_ACCESS;
acl_t facl;
/*
* XXX: ACLs are not supported on whiteouts and device files
* residing on UFS.
*/
if (S_ISCHR(p->fts_statp->st_mode) || S_ISBLK(p->fts_statp->st_mode) ||
S_ISWHT(p->fts_statp->st_mode))
return;
if (previous_dev == p->fts_statp->st_dev && supports_acls == 0)
return;
if (p->fts_level == FTS_ROOTLEVEL)
snprintf(name, sizeof(name), "%s", p->fts_name);
else
snprintf(name, sizeof(name), "%s/%s",
p->fts_parent->fts_accpath, p->fts_name);
if (previous_dev != p->fts_statp->st_dev) {
previous_dev = p->fts_statp->st_dev;
supports_acls = 0;
ret = lpathconf(name, _PC_ACL_NFS4);
if (ret > 0) {
type = ACL_TYPE_NFS4;
supports_acls = 1;
} else if (ret < 0 && errno != EINVAL) {
warn("%s", name);
return;
}
if (supports_acls == 0) {
ret = lpathconf(name, _PC_ACL_EXTENDED);
if (ret > 0) {
type = ACL_TYPE_ACCESS;
supports_acls = 1;
} else if (ret < 0 && errno != EINVAL) {
warn("%s", name);
return;
}
}
}
if (supports_acls == 0)
return;
facl = acl_get_link_np(name, type);
if (facl == NULL) {
warn("%s", name);
return;
}
if (acl_is_trivial_np(facl, &trivial)) {
acl_free(facl);
warn("%s", name);
return;
}
if (!trivial)
buf[10] = '+';
acl_free(facl);
}
Reference in New Issue View Git Blame Copy Permalink