The quilt patch titled Subject: mm: fix vrealloc()'s KASAN poisoning logic has been removed from the -mm tree. Its filename was mm-fix-vreallocs-kasan-poisoning-logic.patch

This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------ 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.

This results in a KASAN splat recorded at [1]. A KASAN mis-reporting issue where there is none.

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 Link: https://lore.kernel.org/bpf/67450f9b.050a0220.21d33d.0004.GAE@google.com/ [1] 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