From: Colin Ian King Date: Fri, 2 Dec 2022 13:51:49 +0000 (+0000) Subject: perf/x86/amd: fix potential integer overflow on shift of a int X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=08245672cdc6505550d1a5020603b0a8d4a6dcc7;p=linux.git 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 Signed-off-by: Peter Zijlstra (Intel) Acked-by: Ian Rogers Acked-by: Kim Phillips Link: https://lore.kernel.org/r/20221202135149.1797974-1-colin.i.king@gmail.com --- diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c index d6f3703e41194..4386b10682ce4 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,