From: Jonas Gorski <jonas.gorski@gmail.com> stable inclusion from stable-v6.6.2 commit d84a038fa4b3073f5045006ed5b8d8eff30de4dc category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8IW7G Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 464bd8ec2f06707f3773676a1bd2c64832a3c805 ] When the membase and pci_dev pointer were moved to a new struct in priv, the actual membase users were left untouched, and they started reading out arbitrary memory behind the struct instead of registers. This unfortunately turned the RNG into a constant number generator, depending on the content of what was at that offset. To fix this, update geode_rng_data_{read,present}() to also get the membase via amd_geode_priv, and properly read from the right addresses again. Fixes: 9f6ec8dc574e ("hwrng: geode - Fix PCI device refcount leak") Reported-by: Timur I. Davletshin <timur.davletshin@gmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217882 Tested-by: Timur I. Davletshin <timur.davletshin@gmail.com> Suggested-by: Jo-Philipp Wich <jo@mein.io> Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/char/hw_random/geode-rng.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/char/hw_random/geode-rng.c b/drivers/char/hw_random/geode-rng.c index 12fbe8091831..159baf00a867 100644 --- a/drivers/char/hw_random/geode-rng.c +++ b/drivers/char/hw_random/geode-rng.c @@ -58,7 +58,8 @@ struct amd_geode_priv { static int geode_rng_data_read(struct hwrng *rng, u32 *data) { - void __iomem *mem = (void __iomem *)rng->priv; + struct amd_geode_priv *priv = (struct amd_geode_priv *)rng->priv; + void __iomem *mem = priv->membase; *data = readl(mem + GEODE_RNG_DATA_REG); @@ -67,7 +68,8 @@ static int geode_rng_data_read(struct hwrng *rng, u32 *data) static int geode_rng_data_present(struct hwrng *rng, int wait) { - void __iomem *mem = (void __iomem *)rng->priv; + struct amd_geode_priv *priv = (struct amd_geode_priv *)rng->priv; + void __iomem *mem = priv->membase; int data, i; for (i = 0; i < 20; i++) { -- 2.25.1