The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 49221cf86d18bb66fe95d3338cb33bd4b9880ca5 Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Date: Tue, 22 Jun 2021 09:15:35 +0200
Subject: [PATCH] fuse: reject internal errno
Don't allow userspace to report errors that could be kernel-internal.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@xxxxxxxxx>
Fixes: 334f485df85a ("[PATCH] FUSE - device functions")
Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.14
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 6e63bcba2a40..b8d58aa08206 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1867,7 +1867,7 @@ static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
}
err = -EINVAL;
- if (oh.error <= -1000 || oh.error > 0)
+ if (oh.error <= -512 || oh.error > 0)
goto copy_finish;
spin_lock(&fpq->lock);
