From: Radu Rendec Date: Thu, 6 Feb 2025 17:44:20 +0000 (-0500) Subject: arm64: cacheinfo: Avoid out-of-bounds write to cacheinfo array X-Git-Tag: v6.14-rc3~30^2~4 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=875d742cf5327c93cba1f11e12b08d3cce7a88d2;p=thirdparty%2Fkernel%2Flinux.git arm64: cacheinfo: Avoid out-of-bounds write to cacheinfo array The loop that detects/populates cache information already has a bounds check on the array size but does not account for cache levels with separate data/instructions cache. Fix this by incrementing the index for any populated leaf (instead of any populated level). Fixes: 5d425c186537 ("arm64: kernel: add support for cpu cache information") Signed-off-by: Radu Rendec Link: https://lore.kernel.org/r/20250206174420.2178724-1-rrendec@redhat.com Signed-off-by: Will Deacon --- diff --git a/arch/arm64/kernel/cacheinfo.c b/arch/arm64/kernel/cacheinfo.c index d9c9218fa1fdd..309942b06c5bc 100644 --- a/arch/arm64/kernel/cacheinfo.c +++ b/arch/arm64/kernel/cacheinfo.c @@ -101,16 +101,18 @@ int populate_cache_leaves(unsigned int cpu) unsigned int level, idx; enum cache_type type; struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); - struct cacheinfo *this_leaf = this_cpu_ci->info_list; + struct cacheinfo *infos = this_cpu_ci->info_list; for (idx = 0, level = 1; level <= this_cpu_ci->num_levels && - idx < this_cpu_ci->num_leaves; idx++, level++) { + idx < this_cpu_ci->num_leaves; level++) { type = get_cache_type(level); if (type == CACHE_TYPE_SEPARATE) { - ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level); - ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level); + if (idx + 1 >= this_cpu_ci->num_leaves) + break; + ci_leaf_init(&infos[idx++], CACHE_TYPE_DATA, level); + ci_leaf_init(&infos[idx++], CACHE_TYPE_INST, level); } else { - ci_leaf_init(this_leaf++, type, level); + ci_leaf_init(&infos[idx++], type, level); } } return 0;