iommu/intel: Fix out-of-bounds memset in dmar_latency_disable()

[ Upstream commit 754f8efe45 ]

dmar_latency_disable() intends to zero out only the single
latency_statistic entry for the given type, but the memset size was
computed as sizeof(*lstat) * DMAR_LATENCY_NUM, which clears the entire
array starting from &lstat[type].

When type > 0, this writes beyond the end of the allocated array,
corrupting adjacent memory.

Fix by using sizeof(*lstat) to clear only the target entry.

Fixes: 55ee5e67a5 ("iommu/vt-d: Add common code for dmar latency performance monitors")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Li RongQing 2026-07-21 17:34:10 +08:00 • committed by Greg Kroah-Hartman
commit 80f3605991