diff options
| author | Miklos Szeredi <mszeredi@suse.cz> | 2010-11-30 16:39:27 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-01-07 13:58:12 -0800 |
| commit | 47c9e56abf97ecbe079bcc50a07b5b49b98b1753 (patch) | |
| tree | 922400b4b8ced10d92048b91e6055912b8a7f9cb /fs | |
| parent | df97163bcad0311ecd0d670d78e59978cc35158e (diff) | |
fuse: verify ioctl retries
commit 7572777eef78ebdee1ecb7c258c0ef94d35bad16 upstream.
Verify that the total length of the iovec returned in FUSE_IOCTL_RETRY
doesn't overflow iov_length().
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/fuse/file.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 9242d294fe90..72cdadef791f 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1627,6 +1627,20 @@ static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, return 0; } +/* Make sure iov_length() won't overflow */ +static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count) +{ + size_t n; + u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT; + + for (n = 0; n < count; n++) { + if (iov->iov_len > (size_t) max) + return -ENOMEM; + max -= iov->iov_len; + } + return 0; +} + /* * For ioctls, there is no generic way to determine how much memory * needs to be read and/or written. Furthermore, ioctls are allowed @@ -1820,6 +1834,14 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, in_iov = page_address(iov_page); out_iov = in_iov + in_iovs; + err = fuse_verify_ioctl_iov(in_iov, in_iovs); + if (err) + goto out; + + err = fuse_verify_ioctl_iov(out_iov, out_iovs); + if (err) + goto out; + goto retry; } |