Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1336562 > unrolled thread

[PATCH] mISDN: prevent possible NULL pointer dereference

Back to article view | Back to linux.kernel

Contents

  [PATCH] mISDN: prevent possible NULL pointer dereference Anton Protopopov <a.s.protopopov@gmail.com> - 2016-02-17 17:30 +0100
    Re: [PATCH] mISDN: prevent possible NULL pointer dereference David Miller <davem@davemloft.net> - 2016-02-18 21:10 +0100

#1336562 — [PATCH] mISDN: prevent possible NULL pointer dereference

A return value of the bchannel_get_rxbuf() function is compared with the
positive ENOMEM value instead of the negative -ENOMEM value to detect a
memory allocation problem. Thus, after a possible memory allocation
failure the bc->bch.rx_skb will be NULL which will lead to a NULL
pointer dereference.

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
---
 drivers/isdn/hardware/mISDN/netjet.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/isdn/hardware/mISDN/netjet.c b/drivers/isdn/hardware/mISDN/netjet.c
index 8e29447..afde4ed 100644
--- a/drivers/isdn/hardware/mISDN/netjet.c
+++ b/drivers/isdn/hardware/mISDN/netjet.c
@@ -392,7 +392,7 @@ read_dma(struct tiger_ch *bc, u32 idx, int cnt)
 	}
 	stat = bchannel_get_rxbuf(&bc->bch, cnt);
 	/* only transparent use the count here, HDLC overun is detected later */
-	if (stat == ENOMEM) {
+	if (stat == -ENOMEM) {
 		pr_warning("%s.B%d: No memory for %d bytes\n",
 			   card->name, bc->bch.nr, cnt);
 		return;
-- 
2.6.5

[toc] | [next] | [standalone]

#1337658

From: Anton Protopopov <a.s.protopopov@gmail.com>
Date: Wed, 17 Feb 2016 11:19:56 -0500

> A return value of the bchannel_get_rxbuf() function is compared with the
> positive ENOMEM value instead of the negative -ENOMEM value to detect a
> memory allocation problem. Thus, after a possible memory allocation
> failure the bc->bch.rx_skb will be NULL which will lead to a NULL
> pointer dereference.
> 
> Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>

Applied.

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web