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.
Fixes: 3ddc2fefe6f3 ("mm: vmalloc: implement vrealloc()")
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
---
mm/vmalloc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 7ed39d104201..f009b21705c1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -4093,7 +4093,8 @@ void *vrealloc_noprof(const void *p, size_t size, gfp_t flags)
/* 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;
}
--
2.43.5
