[PATCH 4.9 083/175] mips: cdmm: fix use-after-free in mips_cdmm_bus_discover

Greg Kroah-Hartman
2020-12-28T13:02:58Z

From: Qinglang Miao <miaoqinglang@huawei.com>

[ Upstream commit f0e82242b16826077a2775eacfe201d803bb7a22 ]

kfree(dev) has been called inside put_device so anther
kfree would cause a use-after-free bug/

Fixes: 8286ae03308c ("MIPS: Add CDMM bus support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/bus/mips_cdmm.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/bus/mips_cdmm.c b/drivers/bus/mips_cdmm.c
index 1b14256376d24..7c1da45be166e 100644
--- a/drivers/bus/mips_cdmm.c
+++ b/drivers/bus/mips_cdmm.c
@@ -544,10 +544,8 @@ static void mips_cdmm_bus_discover(struct mips_cdmm_bus *bus)
dev_set_name(&dev->dev, "cdmm%u-%u", cpu, id);
++id;
ret = device_register(&dev->dev);
- if (ret) {
+ if (ret)
put_device(&dev->dev);
- kfree(dev);
- }
}
}

--
2.27.0