summaryrefslogtreecommitdiffstats
path: root/tools/virtiofsd/passthrough_ll.c
diff options
context:
space:
mode:
authorStefan Hajnoczi2019-03-05 10:32:49 +0100
committerDr. David Alan Gilbert2020-01-23 17:41:36 +0100
commit752272da2b68a2312f0e11fc5303015a6c3ee1ac (patch)
tree9ce46e3e49987b7c2e8c4e87d60530377d38f869 /tools/virtiofsd/passthrough_ll.c
parentvirtiofsd: prevent ".." escape in lo_do_lookup() (diff)
downloadqemu-752272da2b68a2312f0e11fc5303015a6c3ee1ac.tar.gz
qemu-752272da2b68a2312f0e11fc5303015a6c3ee1ac.tar.xz
qemu-752272da2b68a2312f0e11fc5303015a6c3ee1ac.zip
virtiofsd: prevent ".." escape in lo_do_readdir()
Construct a fake dirent for the root directory's ".." entry. This hides the parent directory from the FUSE client. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Diffstat (limited to 'tools/virtiofsd/passthrough_ll.c')
-rw-r--r--tools/virtiofsd/passthrough_ll.c36
1 files changed, 22 insertions, 14 deletions
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index 79d5966eea..e3d65c3676 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -1149,19 +1149,25 @@ out_err:
static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
off_t offset, struct fuse_file_info *fi, int plus)
{
+ struct lo_data *lo = lo_data(req);
struct lo_dirp *d;
+ struct lo_inode *dinode;
char *buf = NULL;
char *p;
size_t rem = size;
- int err = ENOMEM;
+ int err = EBADF;
- (void)ino;
+ dinode = lo_inode(req, ino);
+ if (!dinode) {
+ goto error;
+ }
d = lo_dirp(req, fi);
if (!d) {
goto error;
}
+ err = ENOMEM;
buf = calloc(1, size);
if (!buf) {
goto error;
@@ -1192,15 +1198,21 @@ static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
}
nextoff = d->entry->d_off;
name = d->entry->d_name;
+
fuse_ino_t entry_ino = 0;
+ struct fuse_entry_param e = (struct fuse_entry_param){
+ .attr.st_ino = d->entry->d_ino,
+ .attr.st_mode = d->entry->d_type << 12,
+ };
+
+ /* Hide root's parent directory */
+ if (dinode == &lo->root && strcmp(name, "..") == 0) {
+ e.attr.st_ino = lo->root.ino;
+ e.attr.st_mode = DT_DIR << 12;
+ }
+
if (plus) {
- struct fuse_entry_param e;
- if (is_dot_or_dotdot(name)) {
- e = (struct fuse_entry_param){
- .attr.st_ino = d->entry->d_ino,
- .attr.st_mode = d->entry->d_type << 12,
- };
- } else {
+ if (!is_dot_or_dotdot(name)) {
err = lo_do_lookup(req, ino, name, &e);
if (err) {
goto error;
@@ -1210,11 +1222,7 @@ static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size,
entsize = fuse_add_direntry_plus(req, p, rem, name, &e, nextoff);
} else {
- struct stat st = {
- .st_ino = d->entry->d_ino,
- .st_mode = d->entry->d_type << 12,
- };
- entsize = fuse_add_direntry(req, p, rem, name, &st, nextoff);
+ entsize = fuse_add_direntry(req, p, rem, name, &e.attr, nextoff);
}
if (entsize > rem) {
if (entry_ino != 0) {