From d22f4f977236f97e01255a80bca2ea93a8094fc8 Mon Sep 17 00:00:00 2001 From: Karsten Graul Date: Fri, 8 Apr 2022 17:10:34 +0200 Subject: [PATCH] net/smc: Fix NULL pointer dereference in smc_pnet_find_ib() dev_name() was called with dev.parent as argument but without to NULL-check it before. Solve this by checking the pointer before the call to dev_name(). Fixes: af5f60c7e3d5 ("net/smc: allow PCI IDs as ib device names in the pnet table") Reported-by: syzbot+03e3e228510223dabd34@syzkaller.appspotmail.com Signed-off-by: Karsten Graul Signed-off-by: Jakub Kicinski --- net/smc/smc_pnet.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c index 7984f8883472..7055ed10e316 100644 --- a/net/smc/smc_pnet.c +++ b/net/smc/smc_pnet.c @@ -311,8 +311,9 @@ static struct smc_ib_device *smc_pnet_find_ib(char *ib_name) list_for_each_entry(ibdev, &smc_ib_devices.list, list) { if (!strncmp(ibdev->ibdev->name, ib_name, sizeof(ibdev->ibdev->name)) || - !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name, - IB_DEVICE_NAME_MAX - 1)) { + (ibdev->ibdev->dev.parent && + !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name, + IB_DEVICE_NAME_MAX - 1))) { goto out; } }