1. The file paths being sent and received were not "sanitized" to
ensure that there weren't any ".." components that would escape the
top level directory. This can't happen with the standard rsync
client, but it could be exploited on both read and write if someone
modified an rsync client. This fix sanitizes all incoming and
outgoing paths when "use chroot = no".
2. If a module is also "read only = no", clients could have created
symbolic links with ".." components that would allow writing
outside of the module. This could happen with the standard rsync
client. This fix sanitizes all incoming symbolic link targets
when "use chroot = no".
Previously, only top-level paths (anything passed in command line arguments)
were sanitized. Sorry, I didn't think about the individual file paths
before now.
extern int verbose;
extern int rsync_port;
char *auth_user;
extern int verbose;
extern int rsync_port;
char *auth_user;
int start_socket_client(char *host, char *path, int argc, char *argv[])
{
int start_socket_client(char *host, char *path, int argc, char *argv[])
{
io_printf(fd,"@ERROR: chdir failed\n");
return -1;
}
io_printf(fd,"@ERROR: chdir failed\n");
return -1;
}
request = strdup(p);
start_glob++;
}
request = strdup(p);
start_glob++;
}
- glob_expand(name, argv, &argc, MAX_ARGS, !use_chroot);
+ glob_expand(name, argv, &argc, MAX_ARGS);
/*
* Note that this is applied to all parameters, whether or not
* they are filenames, but no other legal parameters contain
/*
* Note that this is applied to all parameters, whether or not
* they are filenames, but no other legal parameters contain
* and which aren't.
*/
for (i = 1; i < argc; i++) {
* and which aren't.
*/
for (i = 1; i < argc; i++) {
- sanitize_path(argv[i]);
+ sanitize_path(argv[i], NULL);
extern int copy_unsafe_links;
extern int remote_version;
extern int io_error;
extern int copy_unsafe_links;
extern int remote_version;
extern int io_error;
+extern int sanitize_paths;
static char topsrcname[MAXPATHLEN];
static char topsrcname[MAXPATHLEN];
+ if (sanitize_paths) {
+ sanitize_path(thisname, NULL);
+ }
+
if ((p = strrchr(thisname,'/'))) {
static char *lastdir;
*p = 0;
if ((p = strrchr(thisname,'/'))) {
static char *lastdir;
*p = 0;
file->link = (char *)malloc(l+1);
if (!file->link) out_of_memory("receive_file_entry 2");
read_sbuf(f,file->link,l);
file->link = (char *)malloc(l+1);
if (!file->link) out_of_memory("receive_file_entry 2");
read_sbuf(f,file->link,l);
+ if (sanitize_paths) {
+ sanitize_path(file->link, file->dirname);
+ }
strlcpy(cleaned_name, fname, MAXPATHLEN);
cleaned_name[MAXPATHLEN-1] = 0;
clean_fname(cleaned_name);
strlcpy(cleaned_name, fname, MAXPATHLEN);
cleaned_name[MAXPATHLEN-1] = 0;
clean_fname(cleaned_name);
+ if (sanitize_paths) {
+ sanitize_path(cleaned_name, NULL);
+ }
fname = cleaned_name;
memset(sum,0,SUM_LENGTH);
fname = cleaned_name;
memset(sum,0,SUM_LENGTH);
-static void glob_expand_one(char *s, char **argv, int *argc, int maxargs, int sanitize_paths)
+static void glob_expand_one(char *s, char **argv, int *argc, int maxargs)
{
#if !(defined(HAVE_GLOB) && defined(HAVE_GLOB_H))
if (!*s) s = ".";
{
#if !(defined(HAVE_GLOB) && defined(HAVE_GLOB_H))
if (!*s) s = ".";
+ extern int sanitize_paths;
glob_t globbuf;
int i;
if (!*s) s = ".";
glob_t globbuf;
int i;
if (!*s) s = ".";
- s = strdup(s);
- sanitize_path(s);
- argv[*argc] = s;
+ argv[*argc] = strdup(s);
+ if (sanitize_paths) {
+ sanitize_path(argv[*argc], NULL);
+ }
memset(&globbuf, 0, sizeof(globbuf));
glob(argv[*argc], 0, NULL, &globbuf);
memset(&globbuf, 0, sizeof(globbuf));
glob(argv[*argc], 0, NULL, &globbuf);
-void glob_expand(char *base1, char **argv, int *argc, int maxargs, int sanitize_paths)
+void glob_expand(char *base1, char **argv, int *argc, int maxargs)
{
char *s = argv[*argc];
char *p, *q;
{
char *s = argv[*argc];
char *p, *q;
while ((p = strstr(q,base)) && ((*argc) < maxargs)) {
/* split it at this point */
*p = 0;
while ((p = strstr(q,base)) && ((*argc) < maxargs)) {
/* split it at this point */
*p = 0;
- glob_expand_one(q, argv, argc, maxargs, sanitize_paths);
+ glob_expand_one(q, argv, argc, maxargs);
- if (*q && (*argc < maxargs)) glob_expand_one(q, argv, argc, maxargs, sanitize_paths);
+ if (*q && (*argc < maxargs)) glob_expand_one(q, argv, argc, maxargs);
/*
* Make path appear as if a chroot had occurred:
* 1. remove leading "/" (or replace with "." if at end)
/*
* Make path appear as if a chroot had occurred:
* 1. remove leading "/" (or replace with "." if at end)
- * 2. remove leading ".." components
+ * 2. remove leading ".." components (except those allowed by "reldir")
* 3. delete any other "<dir>/.." (recursively)
* 3. delete any other "<dir>/.." (recursively)
+ * If "reldir" is non-null, it is a sanitized directory that the path will be
+ * relative to, so allow as many ".." at the beginning of the path as
+ * there are components in reldir.
* While we're at it, remove double slashes and "." components like
* clean_fname does(), but DON'T remove a trailing slash because that
* is sometimes significant on command line arguments.
* While we're at it, remove double slashes and "." components like
* clean_fname does(), but DON'T remove a trailing slash because that
* is sometimes significant on command line arguments.
* Contributed by Dave Dykstra <dwd@bell-labs.com>
*/
* Contributed by Dave Dykstra <dwd@bell-labs.com>
*/
-void sanitize_path(char *p)
+void sanitize_path(char *p, char *reldir)
+ int depth = 0;
+ int allowdotdot = 0;
+ if (reldir) {
+ depth++;
+ while (*reldir) {
+ if (*reldir++ == '/') {
+ depth++;
+ }
+ }
+ }
start = p;
sanp = p;
while (*p == '/') {
start = p;
sanp = p;
while (*p == '/') {
/* skip following slashes */
;
}
/* skip following slashes */
;
}
- } else if ((*p == '.') && (*(p+1) == '.') &&
+ continue;
+ }
+ allowdotdot = 0;
+ if ((*p == '.') && (*(p+1) == '.') &&
((*(p+2) == '/') || (*(p+2) == '\0'))) {
((*(p+2) == '/') || (*(p+2) == '\0'))) {
- /* skip ".." component followed by slash or end */
- p += 2;
- if (*p == '/')
- p++;
- if (sanp != start) {
- /* back up sanp one level */
- --sanp; /* now pointing at slash */
- while ((sanp > start) && (*(sanp - 1) != '/')) {
- /* skip back up to slash */
- sanp--;
+ /* ".." component followed by slash or end */
+ if ((depth > 0) && (sanp == start)) {
+ /* allow depth levels of .. at the beginning */
+ --depth;
+ allowdotdot = 1;
+ } else {
+ p += 2;
+ if (*p == '/')
+ p++;
+ if (sanp != start) {
+ /* back up sanp one level */
+ --sanp; /* now pointing at slash */
+ while ((sanp > start) && (*(sanp - 1) != '/')) {
+ /* skip back up to slash */
+ sanp--;
+ }
- } else {
- while (1) {
- /* copy one component through next slash */
- *sanp++ = *p++;
- if ((*p == '\0') || (*(p-1) == '/')) {
- while (*p == '/') {
- /* skip multiple slashes */
- p++;
- }
- break;
+ }
+ while (1) {
+ /* copy one component through next slash */
+ *sanp++ = *p++;
+ if ((*p == '\0') || (*(p-1) == '/')) {
+ while (*p == '/') {
+ /* skip multiple slashes */
+ p++;
+ if (allowdotdot) {
+ /* move the virtual beginning to leave the .. alone */
+ start = sanp;
+ }
+ if ((sanp == start) && !allowdotdot) {
/* ended up with nothing, so put in "." component */
*sanp++ = '.';
}
/* ended up with nothing, so put in "." component */
*sanp++ = '.';
}