From 3e84f48edfd33b2e209a117c11fb9ce637cc9b67 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 27 Mar 2013 15:20:30 +0000 Subject: [PATCH] vfs/splice: Fix missed checks in new __kernel_write() helper Commit 06ae43f34bcc ("Don't bother with redoing rw_verify_area() from default_file_splice_from()") lost the checks to test existence of the write/aio_write methods. My apologies ;-/ Eventually, we want that in fs/splice.c side of things (no point repeating it for every buffer, after all), but for now this is the obvious minimal fix. Reported-by: Dave Jones Signed-off-by: Al Viro Signed-off-by: Linus Torvalds --- fs/read_write.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/read_write.c b/fs/read_write.c index f7b5a23b804b..e6ddc8dceb96 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -424,6 +424,9 @@ ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t const char __user *p; ssize_t ret; + if (!file->f_op || (!file->f_op->write && !file->f_op->aio_write)) + return -EINVAL; + old_fs = get_fs(); set_fs(get_ds()); p = (__force const char __user *)buf; -- 2.20.1