commit 2d51013ed2f2b6a5d2369b7fbbd989df1f6369e2 tree b0e3f7fef15e3d1e109cffc90a709116b51d4f37 parent a26d79ca81d6e46c445c8db87a89740c9b4d17e9 author Miklos Szeredi <[EMAIL PROTECTED]> 1164481760 -0800 committer Linus Torvalds <[EMAIL PROTECTED]> 1164490113 -0800
[PATCH] fuse: fix Oops in lookup 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 <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Signed-off-by: Andrew Morton <[EMAIL PROTECTED]> Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]> fs/fuse/dir.c | 52 ++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 38 insertions(+), 14 deletions(-) diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index cfc8f81..c71a6c0 100644 --- a/fs/fuse/dir.c +++ b/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; /* Doesn't hurt to "reset" the validity timeout */ @@ -152,25 +153,33 @@ 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; @@ -221,6 +230,7 @@ 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); @@ -229,9 +239,16 @@ 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))) @@ -240,11 +257,11 @@ 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); @@ -388,6 +405,13 @@ 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; @@ -395,24 +419,24 @@ 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; @@ -434,8 +458,8 @@ 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; } - To unsubscribe from this list: send the line "unsubscribe git-commits-head" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html