netdev - [PATCH] ipw2x00: Use struct_size helper instead of open-coded arithmetic

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sat, 17 Jul 2021 16:25:13 +0200
From:   Len Baker <len.baker@....com>
To:     Stanislav Yakovlev <stas.yakovlev@...il.com>,
        Kalle Valo <kvalo@...eaurora.org>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
Cc:     Len Baker <len.baker@....com>, linux-wireless@...r.kernel.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] ipw2x00: Use struct_size helper instead of open-coded arithmetic

Dynamic size calculations (especially multiplication) should not be
performed in memory allocator function arguments due to the risk of them
overflowing. This could lead to values wrapping around and a smaller
allocation being made than the caller was expecting. Using those
allocations could lead to linear overflows of heap memory and other
misbehaviors.

To avoid this scenario, use the struct_size helper.

Signed-off-by: Len Baker <len.baker@....com>
---
 drivers/net/wireless/intel/ipw2x00/libipw_tx.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/ipw2x00/libipw_tx.c b/drivers/net/wireless/intel/ipw2x00/libipw_tx.c
index d9baa2fa603b..36d1e6b2568d 100644
--- a/drivers/net/wireless/intel/ipw2x00/libipw_tx.c
+++ b/drivers/net/wireless/intel/ipw2x00/libipw_tx.c
@@ -179,8 +179,8 @@ static struct libipw_txb *libipw_alloc_txb(int nr_frags, int txb_size,
 {
 	struct libipw_txb *txb;
 	int i;
-	txb = kmalloc(sizeof(struct libipw_txb) + (sizeof(u8 *) * nr_frags),
-		      gfp_mask);
+
+	txb = kmalloc(struct_size(txb, fragments, nr_frags), gfp_mask);
 	if (!txb)
 		return NULL;

--
2.25.1