The patch titled
fuse: fix Oops in lookup
has been added to the -mm tree. Its filename is
fuse-fix-oops-in-lookup.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: fuse: fix Oops in lookup
From: Miklos Szeredi <miklos@xxxxxxxxxx>
Fix bug in certain error paths of lookup routines. The request object was
reused for sending FORGET, which is illegal. This bug could cause an Oops
in 2.6.18. In earlier versions it might silently corrupt memory, but this
is very unlikely.
These error paths are never triggered by libfuse, so this wasn't noticed
even with the 2.6.18 kernel, only with a filesystem using the raw kernel
interface.
Thanks to Russ Cox for the bug report and test filesystem.
Signed-off-by: Miklos Szeredi <miklos@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
fs/fuse/dir.c | 52 +++++++++++++++++++++++++++++++++++-------------
1 files changed, 38 insertions(+), 14 deletions(-)
diff -puN fs/fuse/dir.c~fuse-fix-oops-in-lookup fs/fuse/dir.c
--- a/fs/fuse/dir.c~fuse-fix-oops-in-lookup
+++ a/fs/fuse/dir.c
@@ -138,6 +138,7 @@ static int fuse_dentry_revalidate(struct
struct fuse_entry_out outarg;
struct fuse_conn *fc;
struct fuse_req *req;
+ struct fuse_req *forget_req;
struct dentry *parent;
/* For negative dentries, always do a fresh lookup */
@@ -149,25 +150,33 @@ static int fuse_dentry_revalidate(struct
if (IS_ERR(req))
return 0;
+ forget_req = fuse_get_req(fc);
+ if (IS_ERR(forget_req)) {
+ fuse_put_request(fc, req);
+ return 0;
+ }
+
parent = dget_parent(entry);
fuse_lookup_init(req, parent->d_inode, entry, &outarg);
request_send(fc, req);
dput(parent);
err = req->out.h.error;
+ fuse_put_request(fc, req);
/* Zero nodeid is same as -ENOENT */
if (!err && !outarg.nodeid)
err = -ENOENT;
if (!err) {
struct fuse_inode *fi = get_fuse_inode(inode);
if (outarg.nodeid != get_node_id(inode)) {
- fuse_send_forget(fc, req, outarg.nodeid, 1);
+ fuse_send_forget(fc, forget_req,
+ outarg.nodeid, 1);
return 0;
}
spin_lock(&fc->lock);
fi->nlookup ++;
spin_unlock(&fc->lock);
}
- fuse_put_request(fc, req);
+ fuse_put_request(fc, forget_req);
if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
return 0;
@@ -218,6 +227,7 @@ static struct dentry *fuse_lookup(struct
struct inode *inode = NULL;
struct fuse_conn *fc = get_fuse_conn(dir);
struct fuse_req *req;
+ struct fuse_req *forget_req;
if (entry->d_name.len > FUSE_NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
@@ -226,9 +236,16 @@ static struct dentry *fuse_lookup(struct
if (IS_ERR(req))
return ERR_PTR(PTR_ERR(req));
+ forget_req = fuse_get_req(fc);
+ if (IS_ERR(forget_req)) {
+ fuse_put_request(fc, req);
+ return ERR_PTR(PTR_ERR(forget_req));
+ }
+
fuse_lookup_init(req, dir, entry, &outarg);
request_send(fc, req);
err = req->out.h.error;
+ fuse_put_request(fc, req);
/* Zero nodeid is same as -ENOENT, but with valid timeout */
if (!err && outarg.nodeid &&
(invalid_nodeid(outarg.nodeid) || !valid_mode(outarg.attr.mode)))
@@ -237,11 +254,11 @@ static struct dentry *fuse_lookup(struct
inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation,
&outarg.attr);
if (!inode) {
- fuse_send_forget(fc, req, outarg.nodeid, 1);
+ fuse_send_forget(fc, forget_req, outarg.nodeid, 1);
return ERR_PTR(-ENOMEM);
}
}
- fuse_put_request(fc, req);
+ fuse_put_request(fc, forget_req);
if (err && err != -ENOENT)
return ERR_PTR(err);
@@ -385,6 +402,13 @@ static int create_new_entry(struct fuse_
struct fuse_entry_out outarg;
struct inode *inode;
int err;
+ struct fuse_req *forget_req;
+
+ forget_req = fuse_get_req(fc);
+ if (IS_ERR(forget_req)) {
+ fuse_put_request(fc, req);
+ return PTR_ERR(forget_req);
+ }
req->in.h.nodeid = get_node_id(dir);
req->out.numargs = 1;
@@ -392,24 +416,24 @@ static int create_new_entry(struct fuse_
req->out.args[0].value = &outarg;
request_send(fc, req);
err = req->out.h.error;
- if (err) {
- fuse_put_request(fc, req);
- return err;
- }
+ fuse_put_request(fc, req);
+ if (err)
+ goto out_put_forget_req;
+
err = -EIO;
if (invalid_nodeid(outarg.nodeid))
- goto out_put_request;
+ goto out_put_forget_req;
if ((outarg.attr.mode ^ mode) & S_IFMT)
- goto out_put_request;
+ goto out_put_forget_req;
inode = fuse_iget(dir->i_sb, outarg.nodeid, outarg.generation,
&outarg.attr);
if (!inode) {
- fuse_send_forget(fc, req, outarg.nodeid, 1);
+ fuse_send_forget(fc, forget_req, outarg.nodeid, 1);
return -ENOMEM;
}
- fuse_put_request(fc, req);
+ fuse_put_request(fc, forget_req);
if (S_ISDIR(inode->i_mode)) {
struct dentry *alias;
@@ -431,8 +455,8 @@ static int create_new_entry(struct fuse_
fuse_invalidate_attr(dir);
return 0;
- out_put_request:
- fuse_put_request(fc, req);
+ out_put_forget_req:
+ fuse_put_request(fc, forget_req);
return err;
}
_
Patches currently in -mm which might be from miklos@xxxxxxxxxx are
fuse-fix-oops-in-lookup.patch
fuse-update-userspace-interface-to-version-78.patch
fuse-minor-cleanup-in-fuse_dentry_revalidate.patch
fuse-add-support-for-block-device-based-filesystems.patch
fuse-add-blksize-option.patch
fuse-add-bmap-support.patch
fuse-add-destroy-operation.patch
fuse-depends-on-block.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
