| Message ID | 20200512181921.405973-1-fabf@skynet.be (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fs/notify: cleanup | expand |
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 02a314acc757..63b5dffdca9e 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -487,8 +487,10 @@ static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t group = file->private_data; - if (count > sizeof(response)) - count = sizeof(response); + if (count < sizeof(response)) + return -EINVAL; + + count = sizeof(response); pr_debug("%s: group=%p count=%zu\n", __func__, group, count);
fanotify_write() only aligned copy_from_user size to sizeof(response) for higher values. This patch avoids all values below as suggested by Amir Goldstein and set to response size unconditionally. Signed-off-by: Fabian Frederick <fabf@skynet.be> --- V2: don't write with size under sizeof(response), not only 0 fs/notify/fanotify/fanotify_user.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)