6.6-stable review patch. If anyone has any objections, please let me know.
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From: Andrew Jones ajones@ventanamicro.com
[ Upstream commit e1c05b3bf80f829ced464bdca90f1dfa96e8d251 ]
A hwprobe pair key is signed, but the hwprobe vDSO function was only checking that the upper bound was valid. In order to help avoid this type of problem in the future, and in anticipation of this check becoming more complicated with sparse keys, introduce and use a "key is valid" predicate function for the check.
Fixes: aa5af0aa90ba ("RISC-V: Add hwprobe vDSO function and data") Signed-off-by: Andrew Jones ajones@ventanamicro.com Reviewed-by: Evan Green evan@rivosinc.com Link: https://lore.kernel.org/r/20231010165101.14942-2-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/include/asm/hwprobe.h | 5 +++++ arch/riscv/kernel/vdso/hwprobe.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/hwprobe.h b/arch/riscv/include/asm/hwprobe.h index 78936f4ff5133..7cad513538d8d 100644 --- a/arch/riscv/include/asm/hwprobe.h +++ b/arch/riscv/include/asm/hwprobe.h @@ -10,4 +10,9 @@
#define RISCV_HWPROBE_MAX_KEY 5
+static inline bool riscv_hwprobe_key_is_valid(__s64 key) +{ + return key >= 0 && key <= RISCV_HWPROBE_MAX_KEY; +} + #endif diff --git a/arch/riscv/kernel/vdso/hwprobe.c b/arch/riscv/kernel/vdso/hwprobe.c index d40bec6ac0786..cadf725ef7983 100644 --- a/arch/riscv/kernel/vdso/hwprobe.c +++ b/arch/riscv/kernel/vdso/hwprobe.c @@ -37,7 +37,7 @@ int __vdso_riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
/* This is something we can handle, fill out the pairs. */ while (p < end) { - if (p->key <= RISCV_HWPROBE_MAX_KEY) { + if (riscv_hwprobe_key_is_valid(p->key)) { p->value = avd->all_cpu_hwprobe_values[p->key];
} else {