From 6c60bbbc94b8f086fcb831214fa319ac8117767d Mon Sep 17 00:00:00 2001 From: Jonas Gorski Date: Sat, 9 Sep 2023 12:44:42 +0200 Subject: [PATCH] x86: geode: fix hwrng register accesses 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. Closes #13417. Reported-by: Timur I. Davletshin Tested-by: Timur I. Davletshin Suggested-by: Jo-Philipp Wich Signed-off-by: Jonas Gorski (cherry picked from commit 09d13cd8d87cc50fde67bbe81c6cca4b799b2724) --- ...-hwrng-geode-fix-accessing-registers.patch | 47 +++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 target/linux/x86/patches-5.15/120-hwrng-geode-fix-accessing-registers.patch diff --git a/target/linux/x86/patches-5.15/120-hwrng-geode-fix-accessing-registers.patch b/target/linux/x86/patches-5.15/120-hwrng-geode-fix-accessing-registers.patch new file mode 100644 index 0000000000..4c8015013b --- /dev/null +++ b/target/linux/x86/patches-5.15/120-hwrng-geode-fix-accessing-registers.patch @@ -0,0 +1,47 @@ +From 859bd2e0c0052967536f3f902716f204d5a978b1 Mon Sep 17 00:00:00 2001 +From: Jonas Gorski +Date: Fri, 8 Sep 2023 22:48:33 +0200 +Subject: [PATCH] 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 +Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217882 +Tested-by: Timur I. Davletshin +Suggested-by: Jo-Philipp Wich +Signed-off-by: Jonas Gorski +--- + drivers/char/hw_random/geode-rng.c | 6 ++++-- + 1 file changed, 4 insertions(+), 2 deletions(-) + +--- 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 hw + + 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++) { -- 2.30.2