2013-05-11 16:32:10

by Dan Carpenter

[permalink] [raw]
Subject: [patch] NVMe: check for integer overflow in nvme_map_user_pages()

You need to have CAP_SYS_ADMIN to trigger this overflow but it makes the
static checkers complain so we should fix it. The worry is that
"length" comes from copy_from_user() so we need to check that "length +
offset" can't overflow.

I also changed the min_t() cast to be unsigned instead of signed. Now
that we cap "length" to INT_MAX it doesn't make a difference, but it's a
little easier for reviewers to know that large values aren't cast to
negative.

Signed-off-by: Dan Carpenter <[email protected]>

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 8efdfaa..4376375 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1206,7 +1206,7 @@ struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,

if (addr & 3)
return ERR_PTR(-EINVAL);
- if (!length)
+ if (!length || length > INT_MAX - PAGE_SIZE)
return ERR_PTR(-EINVAL);

offset = offset_in_page(addr);
@@ -1227,7 +1227,8 @@ struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,
sg_init_table(sg, count);
for (i = 0; i < count; i++) {
sg_set_page(&sg[i], pages[i],
- min_t(int, length, PAGE_SIZE - offset), offset);
+ min_t(unsigned, length, PAGE_SIZE - offset),
+ offset);
length -= (PAGE_SIZE - offset);
offset = 0;
}


2013-05-13 13:53:16

by Matthew Wilcox

[permalink] [raw]
Subject: RE: [patch] NVMe: check for integer overflow in nvme_map_user_pages()

Why didn't you send this patch to the linux-nvme mailing list or the address listed in MAINTAINERS? Now Exchange & Outlook have hold of it, and it's mangled.

NVM EXPRESS DRIVER
M: Matthew Wilcox <[email protected]>
L: [email protected]

________________________________________
From: Dan Carpenter [[email protected]]
Sent: May 11, 2013 9:31 AM
To: Wilcox, Matthew R
Cc: Busch, Keith; Verma, Vishal L; [email protected]; [email protected]
Subject: [patch] NVMe: check for integer overflow in nvme_map_user_pages()

You need to have CAP_SYS_ADMIN to trigger this overflow but it makes the
static checkers complain so we should fix it. The worry is that
"length" comes from copy_from_user() so we need to check that "length +
offset" can't overflow.

I also changed the min_t() cast to be unsigned instead of signed. Now
that we cap "length" to INT_MAX it doesn't make a difference, but it's a
little easier for reviewers to know that large values aren't cast to
negative.

Signed-off-by: Dan Carpenter <[email protected]>

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 8efdfaa..4376375 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1206,7 +1206,7 @@ struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,

if (addr & 3)
return ERR_PTR(-EINVAL);
- if (!length)
+ if (!length || length > INT_MAX - PAGE_SIZE)
return ERR_PTR(-EINVAL);

offset = offset_in_page(addr);
@@ -1227,7 +1227,8 @@ struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,
sg_init_table(sg, count);
for (i = 0; i < count; i++) {
sg_set_page(&sg[i], pages[i],
- min_t(int, length, PAGE_SIZE - offset), offset);
+ min_t(unsigned, length, PAGE_SIZE - offset),
+ offset);
length -= (PAGE_SIZE - offset);
offset = 0;
}

2013-05-13 15:00:27

by Dan Carpenter

[permalink] [raw]
Subject: [patch -resend] NVMe: check for integer overflow in nvme_map_user_pages()

You need to have CAP_SYS_ADMIN to trigger this overflow but it makes the
static checkers complain so we should fix it. The worry is that
"length" comes from copy_from_user() so we need to check that "length +
offset" can't overflow.

I also changed the min_t() cast to be unsigned instead of signed. Now
that we cap "length" to INT_MAX it doesn't make a difference, but it's a
little easier for reviewers to know that large values aren't cast to
negative.

Signed-off-by: Dan Carpenter <[email protected]>
---
Resending to the [email protected] email address.

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 8efdfaa..4376375 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1206,7 +1206,7 @@ struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,

if (addr & 3)
return ERR_PTR(-EINVAL);
- if (!length)
+ if (!length || length > INT_MAX - PAGE_SIZE)
return ERR_PTR(-EINVAL);

offset = offset_in_page(addr);
@@ -1227,7 +1227,8 @@ struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,
sg_init_table(sg, count);
for (i = 0; i < count; i++) {
sg_set_page(&sg[i], pages[i],
- min_t(int, length, PAGE_SIZE - offset), offset);
+ min_t(unsigned, length, PAGE_SIZE - offset),
+ offset);
length -= (PAGE_SIZE - offset);
offset = 0;
}

2013-05-13 15:01:17

by Dan Carpenter

[permalink] [raw]
Subject: [patch] MAINTAINERS: update NVM EXPRESS DRIVER file list

There isn't an nvme.c file any more. It has been split into multiple
files.

Signed-off-by: Dan Carpenter <[email protected]>

diff --git a/MAINTAINERS b/MAINTAINERS
index 8f190f5..97ec343 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5747,7 +5747,7 @@ M: Matthew Wilcox <[email protected]>
L: [email protected]
T: git git://git.infradead.org/users/willy/linux-nvme.git
S: Supported
-F: drivers/block/nvme.c
+F: drivers/block/nvme*
F: include/linux/nvme.h

OMAP SUPPORT

2013-05-17 13:41:24

by Matthew Wilcox

[permalink] [raw]
Subject: Re: [patch] MAINTAINERS: update NVM EXPRESS DRIVER file list

On Mon, May 13, 2013 at 06:00:42PM +0300, Dan Carpenter wrote:
> There isn't an nvme.c file any more. It has been split into multiple
> files.
>
> Signed-off-by: Dan Carpenter <[email protected]>

Applied

2013-05-17 13:41:32

by Matthew Wilcox

[permalink] [raw]
Subject: Re: [patch -resend] NVMe: check for integer overflow in nvme_map_user_pages()

On Mon, May 13, 2013 at 05:59:50PM +0300, Dan Carpenter wrote:
> You need to have CAP_SYS_ADMIN to trigger this overflow but it makes the
> static checkers complain so we should fix it. The worry is that
> "length" comes from copy_from_user() so we need to check that "length +
> offset" can't overflow.
>
> I also changed the min_t() cast to be unsigned instead of signed. Now
> that we cap "length" to INT_MAX it doesn't make a difference, but it's a
> little easier for reviewers to know that large values aren't cast to
> negative.
>
> Signed-off-by: Dan Carpenter <[email protected]>

Applied