[PATCH] tools/power: intel-speed-select: Fix a read overflow in isst_set_tdp_level_msr()

From: Dan Carpenter
Date: Wed Aug 21 2019 - 03:14:15 EST


The isst_send_msr_command() function will read 8 bytes but we are
passing an address to an int (4 bytes) so it results in a read overflow.

Fixes: 3fb4f7cd472c ("tools/power/x86: A tool to validate Intel Speed Select commands")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
tools/power/x86/intel-speed-select/isst-core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/power/x86/intel-speed-select/isst-core.c b/tools/power/x86/intel-speed-select/isst-core.c
index 8de4ac39a008..f724322856ed 100644
--- a/tools/power/x86/intel-speed-select/isst-core.c
+++ b/tools/power/x86/intel-speed-select/isst-core.c
@@ -190,6 +190,7 @@ int isst_get_get_trl(int cpu, int level, int avx_level, int *trl)

int isst_set_tdp_level_msr(int cpu, int tdp_level)
{
+ unsigned long long level = tdp_level;
int ret;

debug_printf("cpu: tdp_level via MSR %d\n", cpu, tdp_level);
@@ -202,8 +203,7 @@ int isst_set_tdp_level_msr(int cpu, int tdp_level)
if (tdp_level > 2)
return -1; /* invalid value */

- ret = isst_send_msr_command(cpu, 0x64b, 1,
- (unsigned long long *)&tdp_level);
+ ret = isst_send_msr_command(cpu, 0x64b, 1, &level);
if (ret)
return ret;

--
2.20.1