From 8e3bc7c5bbf87e86e9cd652ca2a9166942d86206 Mon Sep 17 00:00:00 2001 From: Zheyu Ma Date: Wed, 2 Mar 2022 20:24:23 +0800 Subject: [PATCH] net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe() commit bd6f1fd5d33dfe5d1b4f2502d3694a7cc13f166d upstream. During driver initialization, the pointer of card info, i.e. the variable 'ci' is required. However, the definition of 'com20020pci_id_table' reveals that this field is empty for some devices, which will cause null pointer dereference when initializing these devices. The following log reveals it: [ 3.973806] KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] [ 3.973819] RIP: 0010:com20020pci_probe+0x18d/0x13e0 [com20020_pci] [ 3.975181] Call Trace: [ 3.976208] local_pci_probe+0x13f/0x210 [ 3.977248] pci_device_probe+0x34c/0x6d0 [ 3.977255] ? pci_uevent+0x470/0x470 [ 3.978265] really_probe+0x24c/0x8d0 [ 3.978273] __driver_probe_device+0x1b3/0x280 [ 3.979288] driver_probe_device+0x50/0x370 Fix this by checking whether the 'ci' is a null pointer first. Fixes: 8c14f9c70327 ("ARCNET: add com20020 PCI IDs with metadata") Signed-off-by: Zheyu Ma Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/arcnet/com20020-pci.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/arcnet/com20020-pci.c b/drivers/net/arcnet/com20020-pci.c index 239de38fbd6a..1c9fff038569 100644 --- a/drivers/net/arcnet/com20020-pci.c +++ b/drivers/net/arcnet/com20020-pci.c @@ -115,6 +115,9 @@ static int com20020pci_probe(struct pci_dev *pdev, return -ENOMEM; ci = (struct com20020_pci_card_info *)id->driver_data; + if (!ci) + return -EINVAL; + priv->ci = ci; mm = &ci->misc_map; -- 2.20.1