From 8eacd1bd21d6913ec27e6120e9a8733352e191d3 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Mon, 8 Oct 2018 14:28:52 -0700 Subject: [PATCH] nvmet: avoid integer overflow in the discard code Although I'm not sure whether it is a good idea to support large discard commands, I think integer overflow for discard ranges larger than 4 GB should be avoided. This patch avoids that smatch reports the following: drivers/nvme/target/io-cmd-file.c:249:1 nvmet_file_execute_discard() warn: should '((range.nlb)) << req->ns->blksize_shift' be a 64 bit type? Fixes: d5eff33ee6f8 ("nvmet: add simple file backed ns support") Signed-off-by: Bart Van Assche Reviewed-by: Chaitanya Kulkarni Signed-off-by: Christoph Hellwig --- drivers/nvme/target/io-cmd-file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c index 81a9dc5..39d972e 100644 --- a/drivers/nvme/target/io-cmd-file.c +++ b/drivers/nvme/target/io-cmd-file.c @@ -246,7 +246,8 @@ static void nvmet_file_execute_discard(struct nvmet_req *req) break; offset = le64_to_cpu(range.slba) << req->ns->blksize_shift; - len = le32_to_cpu(range.nlb) << req->ns->blksize_shift; + len = le32_to_cpu(range.nlb); + len <<= req->ns->blksize_shift; if (offset + len > req->ns->size) { ret = NVME_SC_LBA_RANGE | NVME_SC_DNR; break; -- 2.7.4