[PATCH 5.10 39/77] IB/qib: Protect from buffer overflow in struct qib_user_sdma_pkt fields

Greg Kroah-Hartman
2021-11-01T09:38:19Z

From: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>

commit d39bf40e55e666b5905fdbd46a0dced030ce87be upstream.

Overflowing either addrlimit or bytes_togo can allow userspace to trigger
a buffer overflow of kernel memory. Check for overflows in all the places
doing math on user controlled buffers.

Fixes: f931551bafe1 ("IB/qib: Add new qib driver for QLogic PCIe InfiniBand adapters")
Link: https://lore.kernel.org/r/20211012175519.7298.77738.stgit@awfm-01.cornelisnetworks.com
Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/infiniband/hw/qib/qib_user_sdma.c | 33 ++++++++++++++++++++----------
1 file changed, 23 insertions(+), 10 deletions(-)

--- a/drivers/infiniband/hw/qib/qib_user_sdma.c
+++ b/drivers/infiniband/hw/qib/qib_user_sdma.c
@@ -602,7 +602,7 @@ done:
/*
* How many pages in this iovec element?
*/
-static int qib_user_sdma_num_pages(const struct iovec *iov)
+static size_t qib_user_sdma_num_pages(const struct iovec *iov)
{
const unsigned long addr = (unsigned long) iov->iov_base;
const unsigned long len = iov->iov_len;
@@ -658,7 +658,7 @@ static void qib_user_sdma_free_pkt_frag(
static int qib_user_sdma_pin_pages(const struct qib_devdata *dd,
struct qib_user_sdma_queue *pq,
struct qib_user_sdma_pkt *pkt,
- unsigned long addr, int tlen, int npages)
+ unsigned long addr, int tlen, size_t npages)
{
struct page *pages[8];
int i, j;
@@ -722,7 +722,7 @@ static int qib_user_sdma_pin_pkt(const s
unsigned long idx;

for (idx = 0; idx < niov; idx++) {
- const int npages = qib_user_sdma_num_pages(iov + idx);
+ const size_t npages = qib_user_sdma_num_pages(iov + idx);
const unsigned long addr = (unsigned long) iov[idx].iov_base;

ret = qib_user_sdma_pin_pages(dd, pq, pkt, addr,
@@ -824,8 +824,8 @@ static int qib_user_sdma_queue_pkts(cons
unsigned pktnw;
unsigned pktnwc;
int nfrags = 0;
- int npages = 0;
- int bytes_togo = 0;
+ size_t npages = 0;
+ size_t bytes_togo = 0;
int tiddma = 0;
int cfur;

@@ -885,7 +885,11 @@ static int qib_user_sdma_queue_pkts(cons

npages += qib_user_sdma_num_pages(&iov[idx]);

- bytes_togo += slen;
+ if (check_add_overflow(bytes_togo, slen, &bytes_togo) ||
+ bytes_togo > type_max(typeof(pkt->bytes_togo))) {
+ ret = -EINVAL;
+ goto free_pbc;
+ }
pktnwc += slen >> 2;
idx++;
nfrags++;
@@ -904,8 +908,7 @@ static int qib_user_sdma_queue_pkts(cons
}

if (frag_size) {
- int tidsmsize, n;
- size_t pktsize;
+ size_t tidsmsize, n, pktsize, sz, addrlimit;

n = npages*((2*PAGE_SIZE/frag_size)+1);
pktsize = struct_size(pkt, addr, n);
@@ -923,14 +926,24 @@ static int qib_user_sdma_queue_pkts(cons
else
tidsmsize = 0;

- pkt = kmalloc(pktsize+tidsmsize, GFP_KERNEL);
+ if (check_add_overflow(pktsize, tidsmsize, &sz)) {
+ ret = -EINVAL;
+ goto free_pbc;
+ }
+ pkt = kmalloc(sz, GFP_KERNEL);
if (!pkt) {
ret = -ENOMEM;
goto free_pbc;
}
pkt->largepkt = 1;
pkt->frag_size = frag_size;
- pkt->addrlimit = n + ARRAY_SIZE(pkt->addr);
+ if (check_add_overflow(n, ARRAY_SIZE(pkt->addr),
+ &addrlimit) ||
+ addrlimit > type_max(typeof(pkt->addrlimit))) {
+ ret = -EINVAL;
+ goto free_pbc;
+ }
+ pkt->addrlimit = addrlimit;

if (tiddma) {
char *tidsm = (char *)pkt + pktsize;