[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PULL 047/111] virtiofsd: prevent ".." escape in lo_do_readdir()
From: |
Dr. David Alan Gilbert (git) |
Subject: |
[PULL 047/111] virtiofsd: prevent ".." escape in lo_do_readdir() |
Date: |
Thu, 23 Jan 2020 11:57:37 +0000 |
From: Stefan Hajnoczi <address@hidden>
Construct a fake dirent for the root directory's ".." entry. This hides
the parent directory from the FUSE client.
Signed-off-by: Stefan Hajnoczi <address@hidden>
Reviewed-by: Sergio Lopez <address@hidden>
Signed-off-by: Dr. David Alan Gilbert <address@hidden>
---
tools/virtiofsd/passthrough_ll.c | 36 +++++++++++++++++++-------------
1 file 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) {
--
2.24.1
- [PULL 030/111] virtiofsd: make -f (foreground) the default, (continued)
- [PULL 030/111] virtiofsd: make -f (foreground) the default, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 037/111] virtiofsd: passthrough_ll: add dirp_map to hide lo_dirp pointers, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 038/111] virtiofsd: passthrough_ll: add fd_map to hide file descriptors, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 036/111] virtiofsd: passthrough_ll: add ino_map to hide lo_inode pointers, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 042/111] virtiofsd: Pass write iov's all the way through, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 043/111] virtiofsd: add fuse_mbuf_iter API, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 040/111] virtiofsd: validate path components, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 041/111] virtiofsd: Plumb fuse_bufvec through to do_write_buf, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 039/111] virtiofsd: passthrough_ll: add fallback for racy ops, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 044/111] virtiofsd: validate input buffer sizes in do_write_buf(), Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 047/111] virtiofsd: prevent ".." escape in lo_do_readdir(),
Dr. David Alan Gilbert (git) <=
- [PULL 046/111] virtiofsd: prevent ".." escape in lo_do_lookup(), Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 048/111] virtiofsd: use /proc/self/fd/ O_PATH file descriptor, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 049/111] virtiofsd: sandbox mount namespace, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 053/111] virtiofsd: Parse flag FUSE_WRITE_KILL_PRIV, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 052/111] virtiofsd: add seccomp whitelist, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 045/111] virtiofsd: check input buffer size in fuse_lowlevel.c ops, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 051/111] virtiofsd: move to a new pid namespace, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 054/111] virtiofsd: cap-ng helpers, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 050/111] virtiofsd: move to an empty network namespace, Dr. David Alan Gilbert (git), 2020/01/23
- [PULL 055/111] virtiofsd: Drop CAP_FSETID if client asked for it, Dr. David Alan Gilbert (git), 2020/01/23