RISC-V: hwprobe: Fix vDSO SIGSEGV

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: aa5af0aa90 ("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>
This commit is contained in:
Andrew Jones 2023-10-10 18:51:02 +02:00 committed by Palmer Dabbelt
parent 653301077c
commit e1c05b3bf8
No known key found for this signature in database
GPG Key ID: 2E1319F35FBB1889
2 changed files with 6 additions and 1 deletions

View File

@ -10,4 +10,9 @@
#define RISCV_HWPROBE_MAX_KEY 6
static inline bool riscv_hwprobe_key_is_valid(__s64 key)
{
return key >= 0 && key <= RISCV_HWPROBE_MAX_KEY;
}
#endif

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@ -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 {