The krealloc function checks where the same buffer was reused or a new one allocated by comparing kernel pointers. KHWASAN changes memory tag on the krealloc'ed chunk of memory and therefore also changes the pointer tag of the returned pointer. Therefore we need to perform comparison on untagged (with tags reset) pointers to check whether it's the same memory region or not. Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> --- mm/slab_common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/slab_common.c b/mm/slab_common.c index a33e61315ca6..5911f2194cf7 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -1494,7 +1494,7 @@ void *krealloc(const void *p, size_t new_size, gfp_t flags) } ret = __do_krealloc(p, new_size, flags); - if (ret && p != ret) + if (ret && khwasan_reset_tag(p) != khwasan_reset_tag(ret)) kfree(p); return ret; -- 2.17.0.rc0.231.g781580f067-goog _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
