The patch titled Subject: mm: fix vrealloc()'s KASAN poisoning logic has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-fix-vreallocs-kasan-poisoning-logic.patch
This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...
This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------ From: Andrii Nakryiko andrii@kernel.org Subject: mm: fix vrealloc()'s KASAN poisoning logic Date: Mon, 25 Nov 2024 16:52:06 -0800
When vrealloc() reuses already allocated vmap_area, we need to re-annotate poisoned and unpoisoned portions of underlying memory according to the new size.
Note, hard-coding KASAN_VMALLOC_PROT_NORMAL might not be exactly correct, but KASAN flag logic is pretty involved and spread out throughout __vmalloc_node_range_noprof(), so I'm using the bare minimum flag here and leaving the rest to mm people to refactor this logic and reuse it here.
Link: https://lkml.kernel.org/r/20241126005206.3457974-1-andrii@kernel.org Fixes: 3ddc2fefe6f3 ("mm: vmalloc: implement vrealloc()") Signed-off-by: Andrii Nakryiko andrii@kernel.org Cc: Alexei Starovoitov ast@kernel.org Cc: Christoph Hellwig hch@infradead.org Cc: Michal Hocko mhocko@suse.com Cc: Uladzislau Rezki (Sony) urezki@gmail.com Cc: Vlastimil Babka vbabka@suse.cz Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
mm/vmalloc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/mm/vmalloc.c~mm-fix-vreallocs-kasan-poisoning-logic +++ a/mm/vmalloc.c @@ -4093,7 +4093,8 @@ void *vrealloc_noprof(const void *p, siz /* Zero out spare memory. */ if (want_init_on_alloc(flags)) memset((void *)p + size, 0, old_size - size); - + kasan_poison_vmalloc(p + size, old_size - size); + kasan_unpoison_vmalloc(p, size, KASAN_VMALLOC_PROT_NORMAL); return (void *)p; }
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Patches currently in -mm which might be from andrii@kernel.org are
mm-fix-vreallocs-kasan-poisoning-logic.patch