This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1].
Here the multiplication is obviously safe. However, using kcalloc*() is more appropriate [2] and improves readability. This patch has no effect on runtime behavior. Link: https://github.com/KSPP/linux/issues/162 [1] Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2] Reviewed-by: Gustavo A. R. Silva <gustavo...@kernel.org> Signed-off-by: Erick Archer <erick.arc...@outlook.com> --- Changes in v3: - Update the commit message to better explain the changes. - Rebase against linux-next. Changes in v2: - Add the "Reviewed-by:" tag. - Rebase against linux-next. Previous versions: v1 -> https://lore.kernel.org/linux-hardening/20240116125813.3754-1-erick.arc...@gmx.com v2 -> https://lore.kernel.org/linux-hardening/as8pr02mb7237a07d73d6d15ebf72fd8d8b...@as8pr02mb7237.eurprd02.prod.outlook.com Hi, This is a new try. In the v2 version Ingo explained that this change is nonsense since kzalloc() is a perfectly usable interface and there is no real overflow here. Anyway, if we have the 2-factor form of the allocator, I think it is a good practice to use it. In this version I have updated the commit message to explain that the code is obviusly safe in contrast with the last version where the impression was given that there was a real overlow bug. I hope this patch can be applied this time. Regards, Erick --- arch/x86/events/amd/uncore.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c index 4ccb8fa483e6..61c0a2114183 100644 --- a/arch/x86/events/amd/uncore.c +++ b/arch/x86/events/amd/uncore.c @@ -479,8 +479,8 @@ static int amd_uncore_ctx_init(struct amd_uncore *uncore, unsigned int cpu) goto fail; curr->cpu = cpu; - curr->events = kzalloc_node(sizeof(*curr->events) * - pmu->num_counters, + curr->events = kcalloc_node(pmu->num_counters, + sizeof(*curr->events), GFP_KERNEL, node); if (!curr->events) { kfree(curr); @@ -928,7 +928,7 @@ int amd_uncore_umc_ctx_init(struct amd_uncore *uncore, unsigned int cpu) uncore->num_pmus += group_num_pmus[gid]; } - uncore->pmus = kzalloc(sizeof(*uncore->pmus) * uncore->num_pmus, + uncore->pmus = kcalloc(uncore->num_pmus, sizeof(*uncore->pmus), GFP_KERNEL); if (!uncore->pmus) { uncore->num_pmus = 0; -- 2.25.1
