Change in ...coreboot[master]: libpayload/drivers/timer: Use 64 bits to prevent overflow

[Jacob Garber (Code Review)]

Jacob Garber has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/32223

Change subject: libpayload/drivers/timer: Use 64 bits to prevent overflow
......................................................................

libpayload/drivers/timer: Use 64 bits to prevent overflow

Cast cpu_khz to a 64 bit integer to prevent possible
integer overflow (the multiplication is currently done
using 32 bit math). Similar to 61dac13 (libpayload:
timer: cast cpu_khz to make sure 64bit math is used).

Found-by: Coverity Scan, CID 1261177
Signed-off-by: Jacob Garber 
Change-Id: Iadb0abb7c7cc078f31a6d88d971f5d1b8ac62a9e
---
M payloads/libpayload/drivers/timer/img_pistachio.c
1 file changed, 1 insertion(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/23/32223/1

diff --git a/payloads/libpayload/drivers/timer/img_pistachio.c b/payloads/libpayload/drivers/timer/img_pistachio.c
index 070998f..d11c3ff 100644
--- a/payloads/libpayload/drivers/timer/img_pistachio.c
+++ b/payloads/libpayload/drivers/timer/img_pistachio.c
@@ -18,7 +18,7 @@

uint64_t timer_hz(void)
 {
-	return lib_sysinfo.cpu_khz * 1000;
+	return (uint64_t)lib_sysinfo.cpu_khz * 1000;
 }

uint64_t timer_raw_value(void)

[Paul Menzel (Code Review)]

Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/32223 )

Change subject: libpayload/drivers/timer: Use 64 bits to prevent overflow
......................................................................

Patch Set 1: Code-Review+1

[HAOUAS Elyes (Code Review)]

HAOUAS Elyes has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/32223 )

Change subject: libpayload/drivers/timer: Use 64 bits to prevent overflow
......................................................................

Patch Set 1:

do we need 64 bits also here? :
nano +283 src/arch/x86/cpu.c

[Patrick Georgi (Code Review)]

Patrick Georgi has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/32223 )

Change subject: libpayload/drivers/timer: Use 64 bits to prevent overflow
......................................................................

Patch Set 1: Code-Review+2

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change and it was merged. ( https://review.coreboot.org/c/coreboot/+/32223 )

Change subject: libpayload/drivers/timer: Use 64 bits to prevent overflow
......................................................................

libpayload/drivers/timer: Use 64 bits to prevent overflow

Cast cpu_khz to a 64 bit integer to prevent possible
integer overflow (the multiplication is currently done
using 32 bit math). Similar to 61dac13 (libpayload:
timer: cast cpu_khz to make sure 64bit math is used).

Found-by: Coverity Scan, CID 1261177
Signed-off-by: Jacob Garber 
Change-Id: Iadb0abb7c7cc078f31a6d88d971f5d1b8ac62a9e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32223
Tested-by: build bot (Jenkins) 
Reviewed-by: Paul Menzel 
Reviewed-by: Patrick Georgi 
---
M payloads/libpayload/drivers/timer/img_pistachio.c
1 file changed, 1 insertion(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Patrick Georgi: Looks good to me, approved
  Paul Menzel: Looks good to me, but someone else must approve

diff --git a/payloads/libpayload/drivers/timer/img_pistachio.c b/payloads/libpayload/drivers/timer/img_pistachio.c
index 070998f..d11c3ff 100644
--- a/payloads/libpayload/drivers/timer/img_pistachio.c
+++ b/payloads/libpayload/drivers/timer/img_pistachio.c
@@ -18,7 +18,7 @@

uint64_t timer_hz(void)
 {
-	return lib_sysinfo.cpu_khz * 1000;
+	return (uint64_t)lib_sysinfo.cpu_khz * 1000;
 }

uint64_t timer_raw_value(void)

[Jacob Garber (Code Review)]

Jacob Garber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/32223 )

Change subject: libpayload/drivers/timer: Use 64 bits to prevent overflow
......................................................................

Patch Set 2:
> Patch Set 1:
>
> do we need 64 bits also here? :
> nano +283 src/arch/x86/cpu.c

Hmmm, possibly. How large is an unsigned long in this case? Even if we make the multiplication 64 bits, it will be implicitly cast to 32 bits inside the tsc_info struct anyway.