[PATCH AUTOSEL 4.19 169/671] ipmi: kcs_bmc: handle devm_kasprintf() failure case

From: Sasha Levin
Date: Thu Jan 16 2020 - 12:01:00 EST


From: Nicholas Mc Guire <hofrat@xxxxxxxxx>

[ Upstream commit 42c7c6ef1e6fa5fc0425120f06f045190b1dda2d ]

devm_kasprintf() may return NULL if internal allocation failed so this
assignment is not safe. Moved the error exit path and added the !NULL
which then allows the devres manager to take care of cleanup.

Signed-off-by: Nicholas Mc Guire <hofrat@xxxxxxxxx>
Fixes: cd2315d471f4 ("ipmi: kcs_bmc: don't change device name")
Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Reviewed-by: Haiyue Wang <haiyue.wang@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/char/ipmi/kcs_bmc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/char/ipmi/kcs_bmc.c b/drivers/char/ipmi/kcs_bmc.c
index e6124bd548df..ed4dc3b1843e 100644
--- a/drivers/char/ipmi/kcs_bmc.c
+++ b/drivers/char/ipmi/kcs_bmc.c
@@ -440,12 +440,13 @@ struct kcs_bmc *kcs_bmc_alloc(struct device *dev, int sizeof_priv, u32 channel)
kcs_bmc->data_in = devm_kmalloc(dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
kcs_bmc->data_out = devm_kmalloc(dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
kcs_bmc->kbuffer = devm_kmalloc(dev, KCS_MSG_BUFSIZ, GFP_KERNEL);
- if (!kcs_bmc->data_in || !kcs_bmc->data_out || !kcs_bmc->kbuffer)
- return NULL;

kcs_bmc->miscdev.minor = MISC_DYNAMIC_MINOR;
kcs_bmc->miscdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s%u",
DEVICE_NAME, channel);
+ if (!kcs_bmc->data_in || !kcs_bmc->data_out || !kcs_bmc->kbuffer ||
+ !kcs_bmc->miscdev.name)
+ return NULL;
kcs_bmc->miscdev.fops = &kcs_bmc_fops;

return kcs_bmc;
--
2.20.1