[PATCH] rsync: Patch CVE-2022-29154 - Development

5 Aug 2022

https://www.openwall.com/lists/oss-security/2022/08/02/1
Signed-off-by: Peter Müller peter.mueller@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

diff --git a/lfs/rsync b/lfs/rsync
index f40c28ce2..c27258929 100644
--- a/lfs/rsync
+++ b/lfs/rsync
@@ -34,7 +34,7 @@ DL_FROM    = $(URL_IPFIRE)
 DIR_APP    = $(DIR_SRC)/$(THISAPP)
 TARGET     = $(DIR_INFO)/$(THISAPP)
 PROG       = rsync
-PAK_VER    = 14
+PAK_VER    = 15
DEPS       =
@@ -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
+	# Fix for CVE-2022-29154
+	cd $(DIR_APP) && patch -Np1 < $(DIR_SRC)/src/patches/rsync-CVE-2022-29154.patch
+
    cd $(DIR_APP) && ./configure \
    --prefix=/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@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;
+ 
++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 = { .debug_type = "" };
+ filter_rule_list cvs_filter_list = { .debug_type = " [global CVS]" };
+ filter_rule_list daemon_filter_list = { .debug_type = " [daemon]" };
++filter_rule_list implied_filter_list = { .debug_type = " [implied]" };
+ 
+ int saw_xattr_filter = 0;
++int trust_sender_filter = 0;
+ 
+ /* 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_
+ 	}
+ }
+ 
++/* Each arg the client sends to the remote sender turns into an implied include
++ * 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 = 0, backslash_cnt = 0;
++	int slash_cnt = 1; /* We know we're adding a leading slash. */
++	const char *cp;
++	char *p;
++	if (old_style_args || list_only || filesfrom_host != NULL)
++		return;
++	if (relative_paths) {
++		cp = strstr(arg, "/./");
++		if (cp)
++			arg = cp+3;
++	} else {
++		if ((cp = strrchr(arg, '/')) != NULL)
++			arg = cp + 1;
++	}
++	arg_len = strlen(arg);
++	if (arg_len) {
++		if (strpbrk(arg, "*[?")) {
++			/* We need to add room to escape backslashes if wildcard chars are present. */
++			cp = arg;
++			while ((cp = strchr(cp, '\')) != NULL) {
++				arg_len++;
++				cp++;
++			}
++			saw_wild = 1;
++		}
++		arg_len++; /* Leave room for the prefixed slash */
++		rule = new0(filter_rule);
++		if (!implied_filter_list.head)
++			implied_filter_list.head = implied_filter_list.tail = rule;
++		else {
++			rule->next = implied_filter_list.head;
++			implied_filter_list.head = rule;
++		}
++		rule->rflags = FILTRULE_INCLUDE + (saw_wild ? FILTRULE_WILD : 0);
++		p = rule->pattern = new_array(char, arg_len + 1);
++		*p++ = '/';
++		cp = arg;
++		while (*cp) {
++			switch (*cp) {
++			  case '\':
++				backslash_cnt++;
++				if (saw_wild)
++					*p++ = '\';
++				*p++ = *cp++;
++				break;
++			  case '/':
++				if (p[-1] == '/') /* This is safe because of the initial slash. */
++					break;
++				if (relative_paths) {
++					filter_rule const *ent;
++					int found = 0;
++					*p = '\0';
++					for (ent = implied_filter_list.head; ent; ent = ent->next) {
++						if (ent != rule && strcmp(ent->pattern, rule->pattern) == 0)
++							found = 1;
++					}
++					if (!found) {
++						filter_rule *R_rule = new0(filter_rule);
++						R_rule->rflags = FILTRULE_INCLUDE + (saw_wild ? FILTRULE_WILD : 0);
++						R_rule->pattern = strdup(rule->pattern);
++						R_rule->u.slash_cnt = slash_cnt;
++						R_rule->next = implied_filter_list.head;
++						implied_filter_list.head = R_rule;
++					}
++				}
++				slash_cnt++;
++				*p++ = *cp++;
++				break;
++			  default:
++				*p++ = *cp++;
++				break;
++			}
++		}
++		*p = '\0';
++		rule->u.slash_cnt = slash_cnt;
++		arg = (const char *)rule->pattern;
++	}
++
++	if (recurse || xfer_dirs) {
++		/* Now create a rule with an added "/" & "**" or "*" at the end */
++		rule = new0(filter_rule);
++		if (recurse)
++			rule->rflags = FILTRULE_INCLUDE | FILTRULE_WILD | FILTRULE_WILD2;
++		else
++			rule->rflags = 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 escaped. */
++			p = rule->pattern = new_array(char, arg_len + backslash_cnt + 3 + 1);
++			cp = arg;
++			while (*cp) {
++				if (*cp == '\')
++					*p++ = '\';
++				*p++ = *cp++;
++			}
++		} else {
++			p = rule->pattern = new_array(char, arg_len + 3 + 1);
++			if (arg_len) {
++				memcpy(p, arg, arg_len);
++				p += arg_len;
++			}
++		}
++		if (p[-1] != '/')
++			*p++ = '/';
++		*p++ = '*';
++		if (recurse)
++			*p++ = '*';
++		*p = '\0';
++		rule->u.slash_cnt = slash_cnt + 1;
++		rule->next = implied_filter_list.head;
++		implied_filter_list.head = rule;
++	}
++}
++
+ /* This frees any non-inherited items, leaving just inherited items on the list. */
+ static void pop_filter_list(filter_rule_list *listp)
+ {
+@@ -718,7 +845,7 @@ static void report_filter_result(enum logcode code, char 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!='s'][!(ent->rflags & FILTRULE_INCLUDE)],
++		    w, actions[*w=='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 **rulestr_ptr,
+ 		}
+ 		switch (ch) {
+ 		case ':':
++			trust_sender_filter = 1;
+ 			rule->rflags |= 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];
+ 
+ extern struct chmod_mode_struct *chmod_modes;
+ 
+-extern filter_rule_list filter_list;
+-extern filter_rule_list daemon_filter_list;
++extern filter_rule_list filter_list, implied_filter_list, daemon_filter_list;
+ 
+ #ifdef ICONV_OPTION
+ extern int filesfrom_convert;
+@@ -986,6 +986,19 @@ static struct file_struct *recv_file_entry(int f, struct file_list *flist, int x
+ 		exit_cleanup(RERR_UNSUPPORTED);
+ 	}
+ 
++	if (*thisname != '.' || thisname[1] != '\0') {
++		int filt_flags = S_ISDIR(mode) ? NAME_IS_DIR : NAME_IS_FILE;
++		if (!trust_sender_filter /* a per-dir filter rule means we must trust the sender's filtering */
++		 && filter_list.head && check_filter(&filter_list, FINFO, thisname, filt_flags) < 0) {
++			rprintf(FERROR, "ERROR: rejecting excluded file-list name: %s\n", thisname);
++			exit_cleanup(RERR_PROTOCOL);
++		}
++		if (implied_filter_list.head && check_filter(&implied_filter_list, FINFO, thisname, filt_flags) <= 0) {
++			rprintf(FERROR, "ERROR: rejecting unrequested file-list name: %s\n", thisname);
++			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 != eob) {
+ 			if (*s++ == '\0') {
+ 				ff_xb.len = 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 = ff_xb.buf + ff_xb.pos;
+ 		char *t = ff_xb.buf;
+ 		char *eob = f + len;
++		char *cur = t;
+ 		/* Eliminate any multi-'\0' runs. */
+ 		while (f != eob) {
+ 			if (!(*t++ = *f++)) {
++				add_implied_include(cur);
++				cur = t;
+ 				while (f != eob && *f == '\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;
+ 
+ uid_t our_uid;
+ gid_t our_gid;
+@@ -635,6 +636,7 @@ static pid_t do_cmd(char *cmd, char *machine, char *user, char **remote_argv, in
+ #ifdef ICONV_CONST
+ 		setup_iconv();
+ #endif
++		trust_sender_filter = 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 = 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 = 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 = ".";
+ 			remote_argv[i] = arg;
++			add_implied_include(arg);
+ 		}
+ 	}
+ 
+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);
+ 
+-		if (daemon_filter_list.head && (*fname != '.' || fname[1] != '\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 != '.' || fname[1] != '\0')) {
++			int filt_flags = 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 excluded file: %s\n",
++					fname);
++				exit_cleanup(RERR_PROTOCOL);
++			}
+ 		}
+ 
+ #ifdef SUPPORT_XATTRS
-- 
2.35.3

    