From: Miklos Szeredi mszeredi@redhat.com
commit eb59bd17d2fa6e5e84fba61a5ebdea984222e6d5 upstream.
If a filesystem returns negative inode sizes, future reads on the file were causing the cpu to spin on truncate_pagecache.
Create a helper to validate the attributes. This now does two things:
- check the file mode - check if the file size fits in i_size without overflowing
Reported-by: Arijit Banerjee arijit@rubrik.com Fixes: d8a5ba45457e ("[PATCH] FUSE - core") Cc: stable@vger.kernel.org # v2.6.14 Signed-off-by: Miklos Szeredi mszeredi@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/fuse/dir.c | 24 +++++++++++++++++------- fs/fuse/fuse_i.h | 2 ++ 2 files changed, 19 insertions(+), 7 deletions(-)
--- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -234,7 +234,8 @@ static int fuse_dentry_revalidate(struct kfree(forget); if (ret == -ENOMEM) goto out; - if (ret || (outarg.attr.mode ^ inode->i_mode) & S_IFMT) + if (ret || fuse_invalid_attr(&outarg.attr) || + (outarg.attr.mode ^ inode->i_mode) & S_IFMT) goto invalid;
forget_all_cached_acls(inode); @@ -297,6 +298,12 @@ int fuse_valid_type(int m) S_ISBLK(m) || S_ISFIFO(m) || S_ISSOCK(m); }
+bool fuse_invalid_attr(struct fuse_attr *attr) +{ + return !fuse_valid_type(attr->mode) || + attr->size > LLONG_MAX; +} + int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name, struct fuse_entry_out *outarg, struct inode **inode) { @@ -328,7 +335,7 @@ int fuse_lookup_name(struct super_block err = -EIO; if (!outarg->nodeid) goto out_put_forget; - if (!fuse_valid_type(outarg->attr.mode)) + if (fuse_invalid_attr(&outarg->attr)) goto out_put_forget;
*inode = fuse_iget(sb, outarg->nodeid, outarg->generation, @@ -451,7 +458,8 @@ static int fuse_create_open(struct inode goto out_free_ff;
err = -EIO; - if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid)) + if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid) || + fuse_invalid_attr(&outentry.attr)) goto out_free_ff;
ff->fh = outopen.fh; @@ -558,7 +566,7 @@ static int create_new_entry(struct fuse_ goto out_put_forget_req;
err = -EIO; - if (invalid_nodeid(outarg.nodeid)) + if (invalid_nodeid(outarg.nodeid) || fuse_invalid_attr(&outarg.attr)) goto out_put_forget_req;
if ((outarg.attr.mode ^ mode) & S_IFMT) @@ -918,7 +926,8 @@ static int fuse_do_getattr(struct inode args.out.args[0].value = &outarg; err = fuse_simple_request(fc, &args); if (!err) { - if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) { + if (fuse_invalid_attr(&outarg.attr) || + (inode->i_mode ^ outarg.attr.mode) & S_IFMT) { make_bad_inode(inode); err = -EIO; } else { @@ -1230,7 +1239,7 @@ static int fuse_direntplus_link(struct f
if (invalid_nodeid(o->nodeid)) return -EIO; - if (!fuse_valid_type(o->attr.mode)) + if (fuse_invalid_attr(&o->attr)) return -EIO;
fc = get_fuse_conn(dir); @@ -1707,7 +1716,8 @@ int fuse_do_setattr(struct dentry *dentr goto error; }
- if ((inode->i_mode ^ outarg.attr.mode) & S_IFMT) { + if (fuse_invalid_attr(&outarg.attr) || + (inode->i_mode ^ outarg.attr.mode) & S_IFMT) { make_bad_inode(inode); err = -EIO; goto error; --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -909,6 +909,8 @@ void fuse_ctl_remove_conn(struct fuse_co */ int fuse_valid_type(int m);
+bool fuse_invalid_attr(struct fuse_attr *attr); + /** * Is current process allowed to perform filesystem operation? */