Adding debian version 2.36.1-8+deb11u2.debian/2.36.1-8+deb11u2debian

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

9 files changed, 644 insertions, 1 deletions

diff --git a/debian/changelog b/debian/changelog
index 42e0eb4..b421cd2 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,11 @@
+util-linux (2.36.1-8+deb11u2) bullseye-security; urgency=high
+
+  * d/gbp.conf: update for stable release
+  * Add upstream patches to fix CVE-2024-28085 (Closes: #1067849)
+  * No longer install wall, write setgid tty to address CVE-2024-28085
+
+ -- Chris Hofstaedtler <zeha@debian.org>  Thu, 28 Mar 2024 11:09:40 +0100
+
 util-linux (2.36.1-8+deb11u1) bullseye-security; urgency=high
 
   * Non-maintainer upload by the Security Team.
diff --git a/debian/gbp.conf b/debian/gbp.conf
index 1756df7..3f6658c 100644
--- a/debian/gbp.conf
+++ b/debian/gbp.conf
@@ -1,5 +1,5 @@
 [DEFAULT]
-debian-branch = master
+debian-branch = debian/bullseye
 upstream-branch = upstream
 pristine-tar = True
 compression = xz
diff --git a/debian/patches/series b/debian/patches/series
index 467522b..dded791 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -10,3 +10,8 @@ upstream/CVE-2021-37600-sys-utils-ipcutils-be-careful-when-call-calloc.patch
 debian/backport-ul_strtou64-function.patch
 upstream/libmount-fix-UID-check-for-FUSE-umount-CVE-2021-3995.patch
 upstream/libmount-fix-deleted-suffix-issue-CVE-2021-3996.patch
+upstream/write-correctly-handle-wide-characters.patch
+upstream/wall-convert-homebrew-buffering-to-open_memstream.patch
+upstream/wall-use-fputs_careful.patch
+upstream/wall-fix-calloc-cal-Werror-calloc-transposed-args.patch
+upstream/wall-fix-escape-sequence-Injection-CVE-2024-28085.patch
diff --git a/debian/patches/upstream/wall-convert-homebrew-buffering-to-open_memstream.patch b/debian/patches/upstream/wall-convert-homebrew-buffering-to-open_memstream.patch
new file mode 100644
index 0000000..7542b1c
--- /dev/null
+++ b/debian/patches/upstream/wall-convert-homebrew-buffering-to-open_memstream.patch
@@ -0,0 +1,165 @@
+From: =?utf-8?b?0L3QsNCx?= <nabijaczleweli@nabijaczleweli.xyz>
+Date: Wed, 15 Mar 2023 16:16:43 +0100
+Subject: wall: convert homebrew buffering to open_memstream()
+MIME-Version: 1.0
+Content-Type: text/plain; charset="utf-8"
+Content-Transfer-Encoding: 8bit
+
+The struct buffer system duplicates a plethora of standard I/O
+functions (including a fork of fputc_careful())
+and adds a lot of complexity ‒ open_memstream() is standard,
+and fits perfectly into this niche
+---
+ term-utils/wall.c | 94 ++++++++++++-------------------------------------------
+ 1 file changed, 20 insertions(+), 74 deletions(-)
+
+diff --git a/term-utils/wall.c b/term-utils/wall.c
+index 97d9a56..97623b8 100644
+--- a/term-utils/wall.c
++++ b/term-utils/wall.c
+@@ -273,73 +273,22 @@ int main(int argc, char **argv)
+ 	exit(EXIT_SUCCESS);
+ }
+ 
+-struct buffer {
+-	size_t	sz;
+-	size_t	used;
+-	char	*data;
+-};
+-
+-static void buf_enlarge(struct buffer *bs, size_t len)
++static void buf_putc_careful(FILE *fs, int c)
+ {
+-	if (bs->sz == 0 || len > bs->sz - bs->used) {
+-		bs->sz += len < 128 ? 128 : len;
+-		bs->data = xrealloc(bs->data, bs->sz);
+-	}
+-}
+-
+-static void buf_puts(struct buffer *bs, const char *s)
+-{
+-	size_t len = strlen(s);
+-
+-	buf_enlarge(bs, len + 1);
+-	memcpy(bs->data + bs->used, s, len + 1);
+-	bs->used += len;
+-}
+-
+-static void buf_printf(struct buffer *bs, const char *fmt, ...)
+-{
+-	int rc;
+-	va_list ap;
+-	size_t limit;
+-
+-	buf_enlarge(bs, 0);	/* default size */
+-	limit = bs->sz - bs->used;
+-
+-	va_start(ap, fmt);
+-	rc = vsnprintf(bs->data + bs->used, limit, fmt, ap);
+-	va_end(ap);
+-
+-	if (rc >= 0 && (size_t) rc >= limit) {	/* not enough, enlarge */
+-		buf_enlarge(bs, (size_t)rc + 1);
+-		limit = bs->sz - bs->used;
+-		va_start(ap, fmt);
+-		rc = vsnprintf(bs->data  + bs->used, limit, fmt, ap);
+-		va_end(ap);
+-	}
+-
+-	if (rc > 0)
+-		bs->used += rc;
+-}
+-
+-static void buf_putc_careful(struct buffer *bs, int c)
+-{
+-	if (isprint(c) || c == '\a' || c == '\t' || c == '\r' || c == '\n') {
+-		buf_enlarge(bs, 1);
+-		bs->data[bs->used++] = c;
+-	} else if (!c_isascii(c))
+-		buf_printf(bs, "\\%3o", (unsigned char)c);
+-	else {
+-		char tmp[] = { '^', c ^ 0x40, '\0' };
+-		buf_puts(bs, tmp);
+-	}
++	if (isprint(c) || c == '\a' || c == '\t' || c == '\r' || c == '\n')
++		fputc(c, fs);
++	else if (!c_isascii(c))
++		fprintf(fs, "\\%3o", (unsigned char)c);
++	else
++		fputs((char[]){ '^', c ^ 0x40, '\0' }, fs);
+ }
+ 
+ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		     size_t *mbufsize, int print_banner)
+ {
+-	struct buffer _bs = {.used = 0}, *bs = &_bs;
+ 	register int ch, cnt;
+-	char *p, *lbuf;
++	char *p, *lbuf, *retbuf;
++	FILE * fs = open_memstream(&retbuf, mbufsize);
+ 	long line_max;
+ 
+ 	line_max = sysconf(_SC_LINE_MAX);
+@@ -379,15 +328,15 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		 */
+ 		/* snprintf is not always available, but the sprintf's here
+ 		   will not overflow as long as %d takes at most 100 chars */
+-		buf_printf(bs, "\r%*s\r\n", TERM_WIDTH, " ");
++		fprintf(fs, "\r%*s\r\n", TERM_WIDTH, " ");
+ 
+ 		snprintf(lbuf, line_max,
+ 				_("Broadcast message from %s@%s (%s) (%s):"),
+ 				whom, hostname, where, date);
+-		buf_printf(bs, "%-*.*s\007\007\r\n", TERM_WIDTH, TERM_WIDTH, lbuf);
++		fprintf(fs, "%-*.*s\007\007\r\n", TERM_WIDTH, TERM_WIDTH, lbuf);
+ 		free(hostname);
+ 	}
+-	buf_printf(bs, "%*s\r\n", TERM_WIDTH, " ");
++	fprintf(fs, "%*s\r\n", TERM_WIDTH, " ");
+ 
+ 	 if (mvec) {
+ 		/*
+@@ -396,11 +345,11 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		int i;
+ 
+ 		for (i = 0; i < mvecsz; i++) {
+-			buf_puts(bs, mvec[i]);
++			fputs(mvec[i], fs);
+ 			if (i < mvecsz - 1)
+-				buf_puts(bs, " ");
++				fputc(' ', fs);
+ 		}
+-		buf_puts(bs, "\r\n");
++		fputs("\r\n", fs);
+ 	} else {
+ 		/*
+ 		 * read message from <file>
+@@ -428,23 +377,20 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		while (fgets(lbuf, line_max, stdin)) {
+ 			for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
+ 				if (cnt == TERM_WIDTH || ch == '\n') {
+-					for (; cnt < TERM_WIDTH; ++cnt)
+-						buf_puts(bs, " ");
+-					buf_puts(bs, "\r\n");
++					fprintf(fs, "%*s\r\n", TERM_WIDTH - cnt, "");
+ 					cnt = 0;
+ 				}
+ 				if (ch == '\t')
+ 					cnt += (7 - (cnt % 8));
+ 				if (ch != '\n')
+-					buf_putc_careful(bs, ch);
++					buf_putc_careful(fs, ch);
+ 			}
+ 		}
+ 	}
+-	buf_printf(bs, "%*s\r\n", TERM_WIDTH, " ");
++	fprintf(fs, "%*s\r\n", TERM_WIDTH, " ");
+ 
+ 	free(lbuf);
+ 
+-	bs->data[bs->used] = '\0';	/* be paranoid */
+-	*mbufsize = bs->used;
+-	return bs->data;
++	fclose(fs);
++	return retbuf;
+ }
diff --git a/debian/patches/upstream/wall-fix-calloc-cal-Werror-calloc-transposed-args.patch b/debian/patches/upstream/wall-fix-calloc-cal-Werror-calloc-transposed-args.patch
new file mode 100644
index 0000000..8d123f0
--- /dev/null
+++ b/debian/patches/upstream/wall-fix-calloc-cal-Werror-calloc-transposed-args.patch
@@ -0,0 +1,27 @@
+From: Karel Zak <kzak@redhat.com>
+Date: Wed, 17 Jan 2024 12:37:08 +0100
+Subject: wall: fix calloc cal [-Werror=calloc-transposed-args]
+
+term-utils/wall.c:143:37: error: xcalloc sizes specified with sizeof in the earlier argument and not in the later argument [-Werror=calloc-transposed-args]
+  143 |         buf->groups = xcalloc(sizeof(*buf->groups), buf->ngroups);
+      |                                     ^
+term-utils/wall.c:143:37: note: earlier argument should specify number of elements, later size of each element
+
+Signed-off-by: Karel Zak <kzak@redhat.com>
+---
+ term-utils/wall.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/term-utils/wall.c b/term-utils/wall.c
+index fa5e027..16dfb1f 100644
+--- a/term-utils/wall.c
++++ b/term-utils/wall.c
+@@ -134,7 +134,7 @@ static struct group_workspace *init_group_workspace(const char *group)
+ 
+ 	buf->requested_group = get_group_gid(group);
+ 	buf->ngroups = sysconf(_SC_NGROUPS_MAX) + 1;  /* room for the primary gid */
+-	buf->groups = xcalloc(sizeof(*buf->groups), buf->ngroups);
++	buf->groups = xcalloc(buf->ngroups, sizeof(*buf->groups));
+ 
+ 	return buf;
+ }
diff --git a/debian/patches/upstream/wall-fix-escape-sequence-Injection-CVE-2024-28085.patch b/debian/patches/upstream/wall-fix-escape-sequence-Injection-CVE-2024-28085.patch
new file mode 100644
index 0000000..c1160fe
--- /dev/null
+++ b/debian/patches/upstream/wall-fix-escape-sequence-Injection-CVE-2024-28085.patch
@@ -0,0 +1,25 @@
+From: Karel Zak <kzak@redhat.com>
+Date: Thu, 21 Mar 2024 11:16:20 +0100
+Subject: wall: fix escape sequence Injection [CVE-2024-28085]
+
+Let's use for all cases the same output function.
+
+Reported-by: Skyler Ferrante <sjf5462@rit.edu>
+Signed-off-by: Karel Zak <kzak@redhat.com>
+---
+ term-utils/wall.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/term-utils/wall.c b/term-utils/wall.c
+index 16dfb1f..a497d91 100644
+--- a/term-utils/wall.c
++++ b/term-utils/wall.c
+@@ -329,7 +329,7 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		int i;
+ 
+ 		for (i = 0; i < mvecsz; i++) {
+-			fputs(mvec[i], fs);
++			fputs_careful(mvec[i], fs, '^', true, TERM_WIDTH);
+ 			if (i < mvecsz - 1)
+ 				fputc(' ', fs);
+ 		}
diff --git a/debian/patches/upstream/wall-use-fputs_careful.patch b/debian/patches/upstream/wall-use-fputs_careful.patch
new file mode 100644
index 0000000..a817c60
--- /dev/null
+++ b/debian/patches/upstream/wall-use-fputs_careful.patch
@@ -0,0 +1,214 @@
+From: =?utf-8?b?0L3QsNCx?= <nabijaczleweli@nabijaczleweli.xyz>
+Date: Wed, 15 Mar 2023 16:16:48 +0100
+Subject: wall: use fputs_careful()
+
+LINE_MAX only applies to teletypes in canonical mode: when stdin is a
+file, it could still very much tear; start off at 512 for the sprintf(),
+then use getline() like in write.
+
+The line wrapping has one suboptimal edge-case:
+  $ wall < all
+
+  Broadcast message from nabijaczleweli@tarta (pts/4) (Tue Mar 14 22:31:25
+  2023):
+
+  ^N^O^P^Q^R^S^T^U^V^W^X^Y^Z^[^\^]^^^_
+  !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJ
+  KLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~^?\200\201\202\203\204\205\206
+  \207\210\211\212\213\214\215\216\217\220\221\222\223\224\225\226\227\230\231\232
+  \233\234\235\236\237\240\241\242\243\244\245\246\247\250\251\252\253\254\255\256
+  \257\260\261\262\263\264\265\266\267\270\271\272\273\274\275\276\277\300\301\302
+  \303\304\305\306\307\310\311\312\313\314\315\316\317\320\321\322\323\324\325\326
+  \327\330\331\332\333\334\335\336\337\340\341\342\343\344\345\346\347\350\351\352
+  \353\354\355\356\357\360\361\362\363\364\365\366\367\370\371\372\373\374\375\376
+  \377
+but that's a pathological input, and the result is still infinitely
+better than it was before, so fixing that is more trouble than it's
+worth.
+
+Bug-Debian: https://bugs.debian.org/826596
+---
+ include/carefulputc.h | 42 +++++++++++++++++++++++++++++++++---------
+ login-utils/last.c    |  2 +-
+ term-utils/wall.c     | 38 ++++++--------------------------------
+ term-utils/write.c    |  2 +-
+ 4 files changed, 41 insertions(+), 43 deletions(-)
+
+diff --git a/include/carefulputc.h b/include/carefulputc.h
+index 4f74526..51d1c99 100644
+--- a/include/carefulputc.h
++++ b/include/carefulputc.h
+@@ -6,6 +6,7 @@
+ #include <ctype.h>
+ #ifdef HAVE_WIDECHAR
+ #include <wctype.h>
++#include <wchar.h>
+ #endif
+ #include <stdbool.h>
+ 
+@@ -15,18 +16,35 @@
+  * A puts() for use in write and wall (that sometimes are sgid tty).
+  * It avoids control and invalid characters.
+  * The locale of the recipient is nominally unknown,
+- * but it's a solid bet that the encoding is compatible with the author's.
++ * but it's a solid bet that it's compatible with the author's.
++ * Use soft_width=0 to disable wrapping.
+  */
+-static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool cr_lf)
++static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool cr_lf, int soft_width)
+ {
+-	int ret = 0;
++	int ret = 0, col = 0;
+ 
+ 	for (size_t slen = strlen(s); *s; ++s, --slen) {
+-		if (*s == '\n')
++		if (*s == '\t')
++			col += (7 - (col % 8)) - 1;
++		else if (*s == '\r')
++			col = -1;
++		else if (*s == '\a')
++			--col;
++
++		if ((soft_width && col >= soft_width) || *s == '\n') {
++			if (soft_width) {
++				fprintf(fp, "%*s", soft_width - col, "");
++				col = 0;
++			}
+ 			ret = fputs(cr_lf ? "\r\n" : "\n", fp);
+-		else if (isprint(*s) || *s == '\a' || *s == '\t' || *s == '\r')
++			if (*s == '\n' || ret < 0)
++				goto wrote;
++		}
++
++		if (isprint(*s) || *s == '\a' || *s == '\t' || *s == '\r') {
+ 			ret = putc(*s, fp);
+-		else if (!c_isascii(*s)) {
++			++col;
++		} else if (!c_isascii(*s)) {
+ #ifdef HAVE_WIDECHAR
+ 			wchar_t w;
+ 			size_t clen = mbtowc(&w, s, slen);
+@@ -35,21 +53,27 @@ static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool
+ 				case (size_t)-1:  // EILSEQ
+ 					mbtowc(NULL, NULL, 0);
+ 				nonprint:
+-					ret = fprintf(fp, "\\%3hho", *s);
++					col += ret = fprintf(fp, "\\%3hho", *s);
+ 					break;
+ 				default:
+ 					if(!iswprint(w))
+ 						goto nonprint;
+ 					ret = fwrite(s, 1, clen, fp);
++					if (soft_width)
++						col += wcwidth(w);
+ 					s += clen - 1;
+ 					slen -= clen - 1;
+ 					break;
+ 			}
+ #else
+-			ret = fprintf(fp, "\\%3hho", *s);
++			col += ret = fprintf(fp, "\\%3hho", *s);
+ #endif
+-		} else
++		} else {
+ 			ret = fputs((char[]){ ctrl, *s ^ 0x40, '\0' }, fp);
++			col += 2;
++		}
++
++	wrote:
+ 		if (ret < 0)
+ 			return EOF;
+ 	}
+diff --git a/login-utils/last.c b/login-utils/last.c
+index c5984f1..8386f08 100644
+--- a/login-utils/last.c
++++ b/login-utils/last.c
+@@ -550,7 +550,7 @@ static int list(const struct last_control *ctl, struct utmpx *p, time_t logout_t
+ 	/*
+ 	 *	Print out "final" string safely.
+ 	 */
+-	fputs_careful(final, stdout, '*', false);
++	fputs_careful(final, stdout, '*', false, 0);
+ 
+ 	if (len < 0 || (size_t)len >= sizeof(final))
+ 		putchar('\n');
+diff --git a/term-utils/wall.c b/term-utils/wall.c
+index 97623b8..fa5e027 100644
+--- a/term-utils/wall.c
++++ b/term-utils/wall.c
+@@ -273,29 +273,13 @@ int main(int argc, char **argv)
+ 	exit(EXIT_SUCCESS);
+ }
+ 
+-static void buf_putc_careful(FILE *fs, int c)
+-{
+-	if (isprint(c) || c == '\a' || c == '\t' || c == '\r' || c == '\n')
+-		fputc(c, fs);
+-	else if (!c_isascii(c))
+-		fprintf(fs, "\\%3o", (unsigned char)c);
+-	else
+-		fputs((char[]){ '^', c ^ 0x40, '\0' }, fs);
+-}
+-
+ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		     size_t *mbufsize, int print_banner)
+ {
+-	register int ch, cnt;
+-	char *p, *lbuf, *retbuf;
++	char *lbuf, *retbuf;
+ 	FILE * fs = open_memstream(&retbuf, mbufsize);
+-	long line_max;
+-
+-	line_max = sysconf(_SC_LINE_MAX);
+-	if (line_max <= 0)
+-		line_max = 512;
+-
+-	lbuf = xmalloc(line_max);
++	size_t lbuflen = 512;
++	lbuf = xmalloc(lbuflen);
+ 
+ 	if (print_banner == TRUE) {
+ 		char *hostname = xgethostname();
+@@ -330,7 +314,7 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		   will not overflow as long as %d takes at most 100 chars */
+ 		fprintf(fs, "\r%*s\r\n", TERM_WIDTH, " ");
+ 
+-		snprintf(lbuf, line_max,
++		snprintf(lbuf, lbuflen,
+ 				_("Broadcast message from %s@%s (%s) (%s):"),
+ 				whom, hostname, where, date);
+ 		fprintf(fs, "%-*.*s\007\007\r\n", TERM_WIDTH, TERM_WIDTH, lbuf);
+@@ -374,18 +358,8 @@ static char *makemsg(char *fname, char **mvec, int mvecsz,
+ 		/*
+ 		 * Read message from stdin.
+ 		 */
+-		while (fgets(lbuf, line_max, stdin)) {
+-			for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
+-				if (cnt == TERM_WIDTH || ch == '\n') {
+-					fprintf(fs, "%*s\r\n", TERM_WIDTH - cnt, "");
+-					cnt = 0;
+-				}
+-				if (ch == '\t')
+-					cnt += (7 - (cnt % 8));
+-				if (ch != '\n')
+-					buf_putc_careful(fs, ch);
+-			}
+-		}
++		while (getline(&lbuf, &lbuflen, stdin) >= 0)
++			fputs_careful(lbuf, fs, '^', true, TERM_WIDTH);
+ 	}
+ 	fprintf(fs, "%*s\r\n", TERM_WIDTH, " ");
+ 
+diff --git a/term-utils/write.c b/term-utils/write.c
+index 710a58c..1d57fce 100644
+--- a/term-utils/write.c
++++ b/term-utils/write.c
+@@ -276,7 +276,7 @@ static void do_write(const struct write_control *ctl)
+ 		if (signal_received)
+ 			break;
+ 
+-		if (fputs_careful(line, stdout, '^', true) == EOF)
++		if (fputs_careful(line, stdout, '^', true, 0) == EOF)
+ 			err(EXIT_FAILURE, _("carefulputc failed"));
+ 	}
+ 	free(line);
diff --git a/debian/patches/upstream/write-correctly-handle-wide-characters.patch b/debian/patches/upstream/write-correctly-handle-wide-characters.patch
new file mode 100644
index 0000000..f931749
--- /dev/null
+++ b/debian/patches/upstream/write-correctly-handle-wide-characters.patch
@@ -0,0 +1,196 @@
+From: =?utf-8?b?0L3QsNCx?= <nabijaczleweli@nabijaczleweli.xyz>
+Date: Wed, 15 Mar 2023 16:16:31 +0100
+Subject: write: correctly handle wide characters
+MIME-Version: 1.0
+Content-Type: text/plain; charset="utf-8"
+Content-Transfer-Encoding: 8bit
+
+Do this by replacing fputc_careful() (notice that the description said
+it's locale-aware ‒ it very much is /not/), with a fputs_careful() which
+does the same thing, but if it were to output a byte in the \123 format,
+first it checks whether this byte starts a valid multibyte character.
+
+If it does, and that character is printable, write it verbatim.
+This means that
+  echo 'foo åäö ąęćźżń bar' | write nabijaczleweli pts/4
+instead of
+  foo \303\245\303\244\303\266
+  \304\205\304\231\304\207\305\272\305\274\305\204 bar
+yields
+  foo åäö ąęćźżń bar
+or, more realistically, from a message I got earlier today,
+  Filip powiedzia\305\202 \305\274e zap\305\202aci jutro
+becomes
+  Filip powiedział że zapłaci jutro
+
+Invalid/non-printable sequences get processed as before.
+
+Line reading in write must become getline() to avoid dealing with
+partial characters: for example on input consisting solely of
+ąęćźżń, where every {1} is an instance, the output would be
+  {42}ąęć\305\272żń{84}ąęćź\305\274ń{84}ąęćźż\305\204{39}
+with just fixed-512 fgets()
+
+Bug-Debian: https://bugs.debian.org/826596
+---
+ include/carefulputc.h | 62 +++++++++++++++++++++++++++++++++++++--------------
+ login-utils/last.c    |  4 +---
+ term-utils/write.c    | 25 ++++++---------------
+ 3 files changed, 53 insertions(+), 38 deletions(-)
+
+diff --git a/include/carefulputc.h b/include/carefulputc.h
+index f1c0356..4f74526 100644
+--- a/include/carefulputc.h
++++ b/include/carefulputc.h
+@@ -1,31 +1,59 @@
+ #ifndef UTIL_LINUX_CAREFULPUTC_H
+ #define UTIL_LINUX_CAREFULPUTC_H
+ 
+-/*
+- * A putc() for use in write and wall (that sometimes are sgid tty).
+- * It avoids control characters in our locale, and also ASCII control
+- * characters.   Note that the locale of the recipient is unknown.
+-*/
+ #include <stdio.h>
+ #include <string.h>
+ #include <ctype.h>
++#ifdef HAVE_WIDECHAR
++#include <wctype.h>
++#endif
++#include <stdbool.h>
+ 
+ #include "cctype.h"
+ 
+-static inline int fputc_careful(int c, FILE *fp, const char fail)
++/*
++ * A puts() for use in write and wall (that sometimes are sgid tty).
++ * It avoids control and invalid characters.
++ * The locale of the recipient is nominally unknown,
++ * but it's a solid bet that the encoding is compatible with the author's.
++ */
++static inline int fputs_careful(const char * s, FILE *fp, const char ctrl, bool cr_lf)
+ {
+-	int ret;
+-
+-	if (isprint(c) || c == '\a' || c == '\t' || c == '\r' || c == '\n')
+-		ret = putc(c, fp);
+-	else if (!c_isascii(c))
+-		ret = fprintf(fp, "\\%3o", (unsigned char)c);
+-	else {
+-		ret = putc(fail, fp);
+-		if (ret != EOF)
+-			ret = putc(c ^ 0x40, fp);
++	int ret = 0;
++
++	for (size_t slen = strlen(s); *s; ++s, --slen) {
++		if (*s == '\n')
++			ret = fputs(cr_lf ? "\r\n" : "\n", fp);
++		else if (isprint(*s) || *s == '\a' || *s == '\t' || *s == '\r')
++			ret = putc(*s, fp);
++		else if (!c_isascii(*s)) {
++#ifdef HAVE_WIDECHAR
++			wchar_t w;
++			size_t clen = mbtowc(&w, s, slen);
++			switch(clen) {
++				case (size_t)-2:  // incomplete
++				case (size_t)-1:  // EILSEQ
++					mbtowc(NULL, NULL, 0);
++				nonprint:
++					ret = fprintf(fp, "\\%3hho", *s);
++					break;
++				default:
++					if(!iswprint(w))
++						goto nonprint;
++					ret = fwrite(s, 1, clen, fp);
++					s += clen - 1;
++					slen -= clen - 1;
++					break;
++			}
++#else
++			ret = fprintf(fp, "\\%3hho", *s);
++#endif
++		} else
++			ret = fputs((char[]){ ctrl, *s ^ 0x40, '\0' }, fp);
++		if (ret < 0)
++			return EOF;
+ 	}
+-	return (ret < 0) ? EOF : 0;
++	return 0;
+ }
+ 
+ /*
+diff --git a/login-utils/last.c b/login-utils/last.c
+index 9d71ba4..c5984f1 100644
+--- a/login-utils/last.c
++++ b/login-utils/last.c
+@@ -395,7 +395,6 @@ static int list(const struct last_control *ctl, struct utmpx *p, time_t logout_t
+ 	char		final[512];
+ 	char		utline[sizeof(p->ut_line) + 1];
+ 	char		domain[256];
+-	char		*s;
+ 	int		mins, hours, days;
+ 	int		r, len;
+ 	struct last_timefmt *fmt;
+@@ -551,8 +550,7 @@ static int list(const struct last_control *ctl, struct utmpx *p, time_t logout_t
+ 	/*
+ 	 *	Print out "final" string safely.
+ 	 */
+-	for (s = final; *s; s++)
+-		fputc_careful(*s, stdout, '*');
++	fputs_careful(final, stdout, '*', false);
+ 
+ 	if (len < 0 || (size_t)len >= sizeof(final))
+ 		putchar('\n');
+diff --git a/term-utils/write.c b/term-utils/write.c
+index 50f18dc..710a58c 100644
+--- a/term-utils/write.c
++++ b/term-utils/write.c
+@@ -223,21 +223,6 @@ static void signal_handler(int signo)
+ 	signal_received = signo;
+ }
+ 
+-/*
+- * write_line - like fputs(), but makes control characters visible and
+- *     turns \n into \r\n.
+- */
+-static void write_line(char *s)
+-{
+-	while (*s) {
+-		const int c = *s++;
+-
+-		if ((c == '\n' && fputc_careful('\r', stdout, '^') == EOF)
+-		    || fputc_careful(c, stdout, '^') == EOF)
+-			err(EXIT_FAILURE, _("carefulputc failed"));
+-	}
+-}
+-
+ /*
+  * do_write - actually make the connection
+  */
+@@ -247,7 +232,8 @@ static void do_write(const struct write_control *ctl)
+ 	struct passwd *pwd;
+ 	time_t now;
+ 	struct tm *tm;
+-	char *host, line[512];
++	char *host, *line = NULL;
++	size_t linelen = 0;
+ 	struct sigaction sigact;
+ 
+ 	/* Determine our login name(s) before the we reopen() stdout */
+@@ -286,11 +272,14 @@ static void do_write(const struct write_control *ctl)
+ 	free(host);
+ 	printf("\r\n");
+ 
+-	while (fgets(line, sizeof(line), stdin) != NULL) {
++	while (getline(&line, &linelen, stdin) >= 0) {
+ 		if (signal_received)
+ 			break;
+-		write_line(line);
++
++		if (fputs_careful(line, stdout, '^', true) == EOF)
++			err(EXIT_FAILURE, _("carefulputc failed"));
+ 	}
++	free(line);
+ 	printf("EOF\r\n");
+ }
+ 
diff --git a/debian/rules b/debian/rules
index 83d6b34..716702a 100755
--- a/debian/rules
+++ b/debian/rules
@@ -37,6 +37,9 @@ CONFOPTS += --disable-chfn-chsh
 # => bsdmainutils
 CONFOPTS += --disable-cal
 
+# Reduce setgid programs (cf. CVE-2024-28085)
+CONFOPTS += --disable-use-tty-group
+
 # Get the list of binary package, except lib* and *-udeb, from
 # debian/control instead of hardcoding the list when installing
 # bash-completions below.