[PATCH] crypto: crypto4xx: fix a potential double free in ppc4xx_trng_probe

From: Wen Yang
Date: Mon Jul 08 2019 - 02:21:27 EST


There is a possible double free issue in ppc4xx_trng_probe():

85: dev->trng_base = of_iomap(trng, 0);
86: of_node_put(trng); ---> released here
87: if (!dev->trng_base)
88: goto err_out;
...
110: ierr_out:
111: of_node_put(trng); ---> double released here
...

This issue was detected by using the Coccinelle software.
We fix it by removing the unnecessary of_node_put().

Fixes: 5343e674f32 ("crypto4xx: integrate ppc4xx-rng into crypto4xx")
Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Allison Randal <allison@xxxxxxxxxxx>
Cc: Armijn Hemel <armijn@xxxxxxxxxx>
Cc: Julia Lawall <Julia.Lawall@xxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/crypto/amcc/crypto4xx_trng.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/crypto/amcc/crypto4xx_trng.c b/drivers/crypto/amcc/crypto4xx_trng.c
index 02a6bed3..f10a87e 100644
--- a/drivers/crypto/amcc/crypto4xx_trng.c
+++ b/drivers/crypto/amcc/crypto4xx_trng.c
@@ -108,7 +108,6 @@ void ppc4xx_trng_probe(struct crypto4xx_core_device *core_dev)
return;

err_out:
- of_node_put(trng);
iounmap(dev->trng_base);
kfree(rng);
dev->trng_base = NULL;
--
2.9.5