From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Tremer <michael.tremer@ipfire.org>
To: development@lists.ipfire.org
Subject: Re: [PATCH] rsync: Patch CVE-2022-29154
Date: Fri, 05 Aug 2022 17:05:21 +0100
Message-ID: <97A8705A-3A02-418C-9959-41AD82E3D3CA@ipfire.org>
In-Reply-To: <95da7fde-2fe4-0c93-b881-232e143a5d26@ipfire.org>
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Reviewed-by: Michael Tremer <michael.tremer(a)ipfire.org>

Thank you.

> On 5 Aug 2022, at 13:00, Peter M=C3=BCller <peter.mueller(a)ipfire.org> wro=
te:
>=20
> https://www.openwall.com/lists/oss-security/2022/08/02/1
>=20
> Signed-off-by: Peter M=C3=BCller <peter.mueller(a)ipfire.org>
> ---
> lfs/rsync                              |   5 +-
> src/patches/rsync-CVE-2022-29154.patch | 322 +++++++++++++++++++++++++
> 2 files changed, 326 insertions(+), 1 deletion(-)
> create mode 100644 src/patches/rsync-CVE-2022-29154.patch
>=20
> diff --git a/lfs/rsync b/lfs/rsync
> index f40c28ce2..c27258929 100644
> --- a/lfs/rsync
> +++ b/lfs/rsync
> @@ -34,7 +34,7 @@ DL_FROM    =3D $(URL_IPFIRE)
> DIR_APP    =3D $(DIR_SRC)/$(THISAPP)
> TARGET     =3D $(DIR_INFO)/$(THISAPP)
> PROG       =3D rsync
> -PAK_VER    =3D 14
> +PAK_VER    =3D 15
>=20
> DEPS       =3D
>=20
> @@ -85,6 +85,9 @@ $(TARGET) : $(patsubst %,$(DIR_DL)/%,$(objects))
> 	# Replace shebang in rsync-ssl
> 	cd $(DIR_APP) && sed -i -e "s@^#!.*@#!/bin/bash@" rsync-ssl
>=20
> +	# Fix for CVE-2022-29154
> +	cd $(DIR_APP) && patch -Np1 < $(DIR_SRC)/src/patches/rsync-CVE-2022-29154=
.patch
> +
> 	cd $(DIR_APP) && ./configure \
> 	--prefix=3D/usr \
> 	--without-included-popt \
> diff --git a/src/patches/rsync-CVE-2022-29154.patch b/src/patches/rsync-CVE=
-2022-29154.patch
> new file mode 100644
> index 000000000..d3b4499a4
> --- /dev/null
> +++ b/src/patches/rsync-CVE-2022-29154.patch
> @@ -0,0 +1,322 @@
> +commit b7231c7d02cfb65d291af74ff66e7d8c507ee871
> +Author: Wayne Davison <wayne(a)opencoder.net>
> +Date:   Sun Jul 31 16:55:34 2022 -0700
> +
> +    Some extra file-list safety checks.
> +
> +diff --git a/exclude.c b/exclude.c
> +index 39073a0c..b670c8ba 100644
> +--- a/exclude.c
> ++++ b/exclude.c
> +@@ -27,16 +27,22 @@ extern int am_server;
> + extern int am_sender;
> + extern int eol_nulls;
> + extern int io_error;
> ++extern int xfer_dirs;
> ++extern int recurse;
> + extern int local_server;
> + extern int prune_empty_dirs;
> + extern int ignore_perishable;
> ++extern int old_style_args;
> ++extern int relative_paths;
> + extern int delete_mode;
> + extern int delete_excluded;
> + extern int cvs_exclude;
> + extern int sanitize_paths;
> + extern int protocol_version;
> ++extern int list_only;
> + extern int module_id;
> +=20
> ++extern char *filesfrom_host;
> + extern char curr_dir[MAXPATHLEN];
> + extern unsigned int curr_dir_len;
> + extern unsigned int module_dirlen;
> +@@ -44,8 +50,10 @@ extern unsigned int module_dirlen;
> + filter_rule_list filter_list =3D { .debug_type =3D "" };
> + filter_rule_list cvs_filter_list =3D { .debug_type =3D " [global CVS]" };
> + filter_rule_list daemon_filter_list =3D { .debug_type =3D " [daemon]" };
> ++filter_rule_list implied_filter_list =3D { .debug_type =3D " [implied]" };
> +=20
> + int saw_xattr_filter =3D 0;
> ++int trust_sender_filter =3D 0;
> +=20
> + /* Need room enough for ":MODS " prefix plus some room to grow. */
> + #define MAX_RULE_PREFIX (16)
> +@@ -292,6 +300,125 @@ static void add_rule(filter_rule_list *listp, const =
char *pat, unsigned int pat_
> + 	}
> + }
> +=20
> ++/* Each arg the client sends to the remote sender turns into an implied i=
nclude
> ++ * that the receiver uses to validate the file list from the sender. */
> ++void add_implied_include(const char *arg)
> ++{
> ++	filter_rule *rule;
> ++	int arg_len, saw_wild =3D 0, backslash_cnt =3D 0;
> ++	int slash_cnt =3D 1; /* We know we're adding a leading slash. */
> ++	const char *cp;
> ++	char *p;
> ++	if (old_style_args || list_only || filesfrom_host !=3D NULL)
> ++		return;
> ++	if (relative_paths) {
> ++		cp =3D strstr(arg, "/./");
> ++		if (cp)
> ++			arg =3D cp+3;
> ++	} else {
> ++		if ((cp =3D strrchr(arg, '/')) !=3D NULL)
> ++			arg =3D cp + 1;
> ++	}
> ++	arg_len =3D strlen(arg);
> ++	if (arg_len) {
> ++		if (strpbrk(arg, "*[?")) {
> ++			/* We need to add room to escape backslashes if wildcard chars are pre=
sent. */
> ++			cp =3D arg;
> ++			while ((cp =3D strchr(cp, '\\')) !=3D NULL) {
> ++				arg_len++;
> ++				cp++;
> ++			}
> ++			saw_wild =3D 1;
> ++		}
> ++		arg_len++; /* Leave room for the prefixed slash */
> ++		rule =3D new0(filter_rule);
> ++		if (!implied_filter_list.head)
> ++			implied_filter_list.head =3D implied_filter_list.tail =3D rule;
> ++		else {
> ++			rule->next =3D implied_filter_list.head;
> ++			implied_filter_list.head =3D rule;
> ++		}
> ++		rule->rflags =3D FILTRULE_INCLUDE + (saw_wild ? FILTRULE_WILD : 0);
> ++		p =3D rule->pattern =3D new_array(char, arg_len + 1);
> ++		*p++ =3D '/';
> ++		cp =3D arg;
> ++		while (*cp) {
> ++			switch (*cp) {
> ++			  case '\\':
> ++				backslash_cnt++;
> ++				if (saw_wild)
> ++					*p++ =3D '\\';
> ++				*p++ =3D *cp++;
> ++				break;
> ++			  case '/':
> ++				if (p[-1] =3D=3D '/') /* This is safe because of the initial slash. */
> ++					break;
> ++				if (relative_paths) {
> ++					filter_rule const *ent;
> ++					int found =3D 0;
> ++					*p =3D '\0';
> ++					for (ent =3D implied_filter_list.head; ent; ent =3D ent->next) {
> ++						if (ent !=3D rule && strcmp(ent->pattern, rule->pattern) =3D=3D 0)
> ++							found =3D 1;
> ++					}
> ++					if (!found) {
> ++						filter_rule *R_rule =3D new0(filter_rule);
> ++						R_rule->rflags =3D FILTRULE_INCLUDE + (saw_wild ? FILTRULE_WILD : 0=
);
> ++						R_rule->pattern =3D strdup(rule->pattern);
> ++						R_rule->u.slash_cnt =3D slash_cnt;
> ++						R_rule->next =3D implied_filter_list.head;
> ++						implied_filter_list.head =3D R_rule;
> ++					}
> ++				}
> ++				slash_cnt++;
> ++				*p++ =3D *cp++;
> ++				break;
> ++			  default:
> ++				*p++ =3D *cp++;
> ++				break;
> ++			}
> ++		}
> ++		*p =3D '\0';
> ++		rule->u.slash_cnt =3D slash_cnt;
> ++		arg =3D (const char *)rule->pattern;
> ++	}
> ++
> ++	if (recurse || xfer_dirs) {
> ++		/* Now create a rule with an added "/" & "**" or "*" at the end */
> ++		rule =3D new0(filter_rule);
> ++		if (recurse)
> ++			rule->rflags =3D FILTRULE_INCLUDE | FILTRULE_WILD | FILTRULE_WILD2;
> ++		else
> ++			rule->rflags =3D FILTRULE_INCLUDE | FILTRULE_WILD;
> ++		/* A +4 in the len leaves enough room for / * * \0 or / * \0 \0 */
> ++		if (!saw_wild && backslash_cnt) {
> ++			/* We are appending a wildcard, so now the backslashes need to be esca=
ped. */
> ++			p =3D rule->pattern =3D new_array(char, arg_len + backslash_cnt + 3 + =
1);
> ++			cp =3D arg;
> ++			while (*cp) {
> ++				if (*cp =3D=3D '\\')
> ++					*p++ =3D '\\';
> ++				*p++ =3D *cp++;
> ++			}
> ++		} else {
> ++			p =3D rule->pattern =3D new_array(char, arg_len + 3 + 1);
> ++			if (arg_len) {
> ++				memcpy(p, arg, arg_len);
> ++				p +=3D arg_len;
> ++			}
> ++		}
> ++		if (p[-1] !=3D '/')
> ++			*p++ =3D '/';
> ++		*p++ =3D '*';
> ++		if (recurse)
> ++			*p++ =3D '*';
> ++		*p =3D '\0';
> ++		rule->u.slash_cnt =3D slash_cnt + 1;
> ++		rule->next =3D implied_filter_list.head;
> ++		implied_filter_list.head =3D rule;
> ++	}
> ++}
> ++
> + /* This frees any non-inherited items, leaving just inherited items on th=
e list. */
> + static void pop_filter_list(filter_rule_list *listp)
> + {
> +@@ -718,7 +845,7 @@ static void report_filter_result(enum logcode code, ch=
ar const *name,
> + 			      : name_flags & NAME_IS_DIR ? "directory"
> + 			      : "file";
> + 		rprintf(code, "[%s] %sing %s %s because of pattern %s%s%s\n",
> +-		    w, actions[*w!=3D's'][!(ent->rflags & FILTRULE_INCLUDE)],
> ++		    w, actions[*w=3D=3D'g'][!(ent->rflags & FILTRULE_INCLUDE)],
> + 		    t, name, ent->pattern,
> + 		    ent->rflags & FILTRULE_DIRECTORY ? "/" : "", type);
> + 	}
> +@@ -890,6 +1017,7 @@ static filter_rule *parse_rule_tok(const char **rules=
tr_ptr,
> + 		}
> + 		switch (ch) {
> + 		case ':':
> ++			trust_sender_filter =3D 1;
> + 			rule->rflags |=3D FILTRULE_PERDIR_MERGE
> + 				      | FILTRULE_FINISH_SETUP;
> + 			/* FALL THROUGH */
> +diff --git a/flist.c b/flist.c
> +index 1ba306bc..0e6bf782 100644
> +--- a/flist.c
> ++++ b/flist.c
> +@@ -73,6 +73,7 @@ extern int need_unsorted_flist;
> + extern int sender_symlink_iconv;
> + extern int output_needs_newline;
> + extern int sender_keeps_checksum;
> ++extern int trust_sender_filter;
> + extern int unsort_ndx;
> + extern uid_t our_uid;
> + extern struct stats stats;
> +@@ -83,8 +84,7 @@ extern char curr_dir[MAXPATHLEN];
> +=20
> + extern struct chmod_mode_struct *chmod_modes;
> +=20
> +-extern filter_rule_list filter_list;
> +-extern filter_rule_list daemon_filter_list;
> ++extern filter_rule_list filter_list, implied_filter_list, daemon_filter_l=
ist;
> +=20
> + #ifdef ICONV_OPTION
> + extern int filesfrom_convert;
> +@@ -986,6 +986,19 @@ static struct file_struct *recv_file_entry(int f, str=
uct file_list *flist, int x
> + 		exit_cleanup(RERR_UNSUPPORTED);
> + 	}
> +=20
> ++	if (*thisname !=3D '.' || thisname[1] !=3D '\0') {
> ++		int filt_flags =3D S_ISDIR(mode) ? NAME_IS_DIR : NAME_IS_FILE;
> ++		if (!trust_sender_filter /* a per-dir filter rule means we must trust t=
he sender's filtering */
> ++		 && filter_list.head && check_filter(&filter_list, FINFO, thisname, fil=
t_flags) < 0) {
> ++			rprintf(FERROR, "ERROR: rejecting excluded file-list name: %s\n", this=
name);
> ++			exit_cleanup(RERR_PROTOCOL);
> ++		}
> ++		if (implied_filter_list.head && check_filter(&implied_filter_list, FINF=
O, thisname, filt_flags) <=3D 0) {
> ++			rprintf(FERROR, "ERROR: rejecting unrequested file-list name: %s\n", t=
hisname);
> ++			exit_cleanup(RERR_PROTOCOL);
> ++		}
> ++	}
> ++
> + 	if (inc_recurse && S_ISDIR(mode)) {
> + 		if (one_file_system) {
> + 			/* Room to save the dir's device for -x */
> +diff --git a/io.c b/io.c
> +index cf94cee7..a6e3ed30 100644
> +--- a/io.c
> ++++ b/io.c
> +@@ -419,6 +419,7 @@ static void forward_filesfrom_data(void)
> + 		while (s !=3D eob) {
> + 			if (*s++ =3D=3D '\0') {
> + 				ff_xb.len =3D s - sob - 1;
> ++				add_implied_include(sob);
> + 				if (iconvbufs(ic_send, &ff_xb, &iobuf.out, flags) < 0)
> + 					exit_cleanup(RERR_PROTOCOL); /* impossible? */
> + 				write_buf(iobuf.out_fd, s-1, 1); /* Send the '\0'. */
> +@@ -450,9 +451,12 @@ static void forward_filesfrom_data(void)
> + 		char *f =3D ff_xb.buf + ff_xb.pos;
> + 		char *t =3D ff_xb.buf;
> + 		char *eob =3D f + len;
> ++		char *cur =3D t;
> + 		/* Eliminate any multi-'\0' runs. */
> + 		while (f !=3D eob) {
> + 			if (!(*t++ =3D *f++)) {
> ++				add_implied_include(cur);
> ++				cur =3D t;
> + 				while (f !=3D eob && *f =3D=3D '\0')
> + 					f++;
> + 			}
> +diff --git a/main.c b/main.c
> +index 58920a2d..5a7fbdd7 100644
> +--- a/main.c
> ++++ b/main.c
> +@@ -89,6 +89,7 @@ extern int backup_dir_len;
> + extern int basis_dir_cnt;
> + extern int default_af_hint;
> + extern int stdout_format_has_i;
> ++extern int trust_sender_filter;
> + extern struct stats stats;
> + extern char *stdout_format;
> + extern char *logfile_format;
> +@@ -104,7 +105,7 @@ extern char curr_dir[MAXPATHLEN];
> + extern char backup_dir_buf[MAXPATHLEN];
> + extern char *basis_dir[MAX_BASIS_DIRS+1];
> + extern struct file_list *first_flist;
> +-extern filter_rule_list daemon_filter_list;
> ++extern filter_rule_list daemon_filter_list, implied_filter_list;
> +=20
> + uid_t our_uid;
> + gid_t our_gid;
> +@@ -635,6 +636,7 @@ static pid_t do_cmd(char *cmd, char *machine, char *us=
er, char **remote_argv, in
> + #ifdef ICONV_CONST
> + 		setup_iconv();
> + #endif
> ++		trust_sender_filter =3D 1;
> + 	} else if (local_server) {
> + 		/* If the user didn't request --[no-]whole-file, force
> + 		 * it on, but only if we're not batch processing. */
> +@@ -1500,6 +1502,8 @@ static int start_client(int argc, char *argv[])
> + 		char *dummy_host;
> + 		int dummy_port =3D rsync_port;
> + 		int i;
> ++		if (filesfrom_fd < 0)
> ++			add_implied_include(remote_argv[0]);
> + 		/* For remote source, any extra source args must have either
> + 		 * the same hostname or an empty hostname. */
> + 		for (i =3D 1; i < remote_argc; i++) {
> +@@ -1523,6 +1527,7 @@ static int start_client(int argc, char *argv[])
> + 			if (!rsync_port && !*arg) /* Turn an empty arg into a dot dir. */
> + 				arg =3D ".";
> + 			remote_argv[i] =3D arg;
> ++			add_implied_include(arg);
> + 		}
> + 	}
> +=20
> +diff --git a/receiver.c b/receiver.c
> +index b3a69da0..93cf8efd 100644
> +--- a/receiver.c
> ++++ b/receiver.c
> +@@ -593,10 +593,13 @@ int recv_files(int f_in, int f_out, char *local_name)
> + 		if (DEBUG_GTE(RECV, 1))
> + 			rprintf(FINFO, "recv_files(%s)\n", fname);
> +=20
> +-		if (daemon_filter_list.head && (*fname !=3D '.' || fname[1] !=3D '\0')
> +-		 && check_filter(&daemon_filter_list, FLOG, fname, 0) < 0) {
> +-			rprintf(FERROR, "attempt to hack rsync failed.\n");
> +-			exit_cleanup(RERR_PROTOCOL);
> ++		if (daemon_filter_list.head && (*fname !=3D '.' || fname[1] !=3D '\0'))=
 {
> ++			int filt_flags =3D S_ISDIR(file->mode) ? NAME_IS_DIR : NAME_IS_FILE;
> ++			if (check_filter(&daemon_filter_list, FLOG, fname, filt_flags) < 0) {
> ++				rprintf(FERROR, "ERROR: rejecting file transfer request for daemon ex=
cluded file: %s\n",
> ++					fname);
> ++				exit_cleanup(RERR_PROTOCOL);
> ++			}
> + 		}
> +=20
> + #ifdef SUPPORT_XATTRS
> --=20
> 2.35.3


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