4.19-stable review patch. If anyone has any objections, please let me know.
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From: Keith Busch keith.busch@intel.com
commit f55adad601c6a97c8c9628195453e0fb23b4a0ae upstream.
We don't need to zero fill the bio if not using kernel allocated pages.
Fixes: f3587d76da05 ("block: Clear kernel memory before copying to user") # v4.20-rc2 Reported-by: Todd Aiken taiken@mvtech.ca Cc: Laurence Oberman loberman@redhat.com Cc: stable@vger.kernel.org Cc: Bart Van Assche bvanassche@acm.org Tested-by: Laurence Oberman loberman@redhat.com Signed-off-by: Keith Busch keith.busch@intel.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- block/bio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/block/bio.c +++ b/block/bio.c @@ -1262,7 +1262,8 @@ struct bio *bio_copy_user_iov(struct req if (ret) goto cleanup; } else { - zero_fill_bio(bio); + if (bmd->is_our_pages) + zero_fill_bio(bio); iov_iter_advance(iter, bio->bi_iter.bi_size); }