|
 |
1d442b |
From: Stefan Hajnoczi <stefanha@redhat.com>
|
|
|
1d442b |
Date: Mon, 27 Jan 2020 19:01:25 +0000
|
|
|
1d442b |
Subject: [PATCH] virtiofsd: prevent ".." escape in lo_do_readdir()
|
|
|
1d442b |
|
|
|
1d442b |
Construct a fake dirent for the root directory's ".." entry. This hides
|
|
|
1d442b |
the parent directory from the FUSE client.
|
|
|
1d442b |
|
|
|
1d442b |
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
|
|
|
1d442b |
Reviewed-by: Sergio Lopez <slp@redhat.com>
|
|
|
1d442b |
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
|
|
|
1d442b |
(cherry picked from commit 752272da2b68a2312f0e11fc5303015a6c3ee1ac)
|
|
|
1d442b |
---
|
|
|
1d442b |
tools/virtiofsd/passthrough_ll.c | 36 +++++++++++++++++++-------------
|
|
|
1d442b |
1 file changed, 22 insertions(+), 14 deletions(-)
|
|
|
1d442b |
|
|
|
1d442b |
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
|
|
|
1d442b |
index 79d5966eea..e3d65c3676 100644
|
|
|
1d442b |
--- a/tools/virtiofsd/passthrough_ll.c
|
|
|
1d442b |
+++ b/tools/virtiofsd/passthrough_ll.c
|
|
|
1d442b |
@@ -1149,19 +1149,25 @@ out_err:
|
|
|
1d442b |
static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
|
|
|
1d442b |
off_t offset, struct fuse_file_info *fi, int plus)
|
|
|
1d442b |
{
|
|
|
1d442b |
+ struct lo_data *lo = lo_data(req);
|
|
|
1d442b |
struct lo_dirp *d;
|
|
|
1d442b |
+ struct lo_inode *dinode;
|
|
|
1d442b |
char *buf = NULL;
|
|
|
1d442b |
char *p;
|
|
|
1d442b |
size_t rem = size;
|
|
|
1d442b |
- int err = ENOMEM;
|
|
|
1d442b |
+ int err = EBADF;
|
|
|
1d442b |
|
|
|
1d442b |
- (void)ino;
|
|
|
1d442b |
+ dinode = lo_inode(req, ino);
|
|
|
1d442b |
+ if (!dinode) {
|
|
|
1d442b |
+ goto error;
|
|
|
1d442b |
+ }
|
|
|
1d442b |
|
|
|
1d442b |
d = lo_dirp(req, fi);
|
|
|
1d442b |
if (!d) {
|
|
|
1d442b |
goto error;
|
|
|
1d442b |
}
|
|
|
1d442b |
|
|
|
1d442b |
+ err = ENOMEM;
|
|
|
1d442b |
buf = calloc(1, size);
|
|
|
1d442b |
if (!buf) {
|
|
|
1d442b |
goto error;
|
|
|
1d442b |
@@ -1192,15 +1198,21 @@ static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
|
|
|
1d442b |
}
|
|
|
1d442b |
nextoff = d->entry->d_off;
|
|
|
1d442b |
name = d->entry->d_name;
|
|
|
1d442b |
+
|
|
|
1d442b |
fuse_ino_t entry_ino = 0;
|
|
|
1d442b |
+ struct fuse_entry_param e = (struct fuse_entry_param){
|
|
|
1d442b |
+ .attr.st_ino = d->entry->d_ino,
|
|
|
1d442b |
+ .attr.st_mode = d->entry->d_type << 12,
|
|
|
1d442b |
+ };
|
|
|
1d442b |
+
|
|
|
1d442b |
+ /* Hide root's parent directory */
|
|
|
1d442b |
+ if (dinode == &lo->root && strcmp(name, "..") == 0) {
|
|
|
1d442b |
+ e.attr.st_ino = lo->root.ino;
|
|
|
1d442b |
+ e.attr.st_mode = DT_DIR << 12;
|
|
|
1d442b |
+ }
|
|
|
1d442b |
+
|
|
|
1d442b |
if (plus) {
|
|
|
1d442b |
- struct fuse_entry_param e;
|
|
|
1d442b |
- if (is_dot_or_dotdot(name)) {
|
|
|
1d442b |
- e = (struct fuse_entry_param){
|
|
|
1d442b |
- .attr.st_ino = d->entry->d_ino,
|
|
|
1d442b |
- .attr.st_mode = d->entry->d_type << 12,
|
|
|
1d442b |
- };
|
|
|
1d442b |
- } else {
|
|
|
1d442b |
+ if (!is_dot_or_dotdot(name)) {
|
|
|
1d442b |
err = lo_do_lookup(req, ino, name, &e);
|
|
|
1d442b |
if (err) {
|
|
|
1d442b |
goto error;
|
|
|
1d442b |
@@ -1210,11 +1222,7 @@ static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
|
|
|
1d442b |
|
|
|
1d442b |
entsize = fuse_add_direntry_plus(req, p, rem, name, &e, nextoff);
|
|
|
1d442b |
} else {
|
|
|
1d442b |
- struct stat st = {
|
|
|
1d442b |
- .st_ino = d->entry->d_ino,
|
|
|
1d442b |
- .st_mode = d->entry->d_type << 12,
|
|
|
1d442b |
- };
|
|
|
1d442b |
- entsize = fuse_add_direntry(req, p, rem, name, &st, nextoff);
|
|
|
1d442b |
+ entsize = fuse_add_direntry(req, p, rem, name, &e.attr, nextoff);
|
|
|
1d442b |
}
|
|
|
1d442b |
if (entsize > rem) {
|
|
|
1d442b |
if (entry_ino != 0) {
|