The following commit has been merged into the perf/urgent branch of tip:
Commit-ID: 08245672cdc6505550d1a5020603b0a8d4a6dcc7
Gitweb: https://git.kernel.org/tip/08245672cdc6505550d1a5020603b0a8d4a6dcc7
Author: Colin Ian King <colin.i.king@xxxxxxxxx>
AuthorDate: Fri, 02 Dec 2022 13:51:49
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Tue, 27 Dec 2022 12:44:00 +01:00
perf/x86/amd: fix potential integer overflow on shift of a int
The left shift of int 32 bit integer constant 1 is evaluated using 32 bit
arithmetic and then passed as a 64 bit function argument. In the case where
i is 32 or more this can lead to an overflow. Avoid this by shifting
using the BIT_ULL macro instead.
Fixes: 471af006a747 ("perf/x86/amd: Constrain Large Increment per Cycle events")
Signed-off-by: Colin Ian King <colin.i.king@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Ian Rogers <irogers@xxxxxxxxxx>
Acked-by: Kim Phillips <kim.phillips@xxxxxxx>
Link: https://lore.kernel.org/r/20221202135149.1797974-1-colin.i.king@xxxxxxxxx
---
arch/x86/events/amd/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index d6f3703..4386b10 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -1387,7 +1387,7 @@ static int __init amd_core_pmu_init(void)
* numbered counter following it.
*/
for (i = 0; i < x86_pmu.num_counters - 1; i += 2)
- even_ctr_mask |= 1 << i;
+ even_ctr_mask |= BIT_ULL(i);
pair_constraint = (struct event_constraint)
__EVENT_CONSTRAINT(0, even_ctr_mask, 0,
|