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| author | Jonas Gorski <jonas.gorski@gmail.com> | 2023-09-10 10:34:17 +0200 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2023-09-15 18:29:46 +0800 |
| commit | 464bd8ec2f06707f3773676a1bd2c64832a3c805 (patch) | |
| tree | 2e73ff7c06bf397902f3de78658c54bc084fdaeb /drivers/char | |
| parent | 453b3d0278d73e355bedce47147663070004e807 (diff) | |
| download | linux-464bd8ec2f06707f3773676a1bd2c64832a3c805.tar.gz | |
hwrng: geode - fix accessing registers
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>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/hw_random/geode-rng.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/char/hw_random/geode-rng.c b/drivers/char/hw_random/geode-rng.c index 12fbe80918319..159baf00a8675 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++) { |