Hi,
在 2023/04/27 16:56, linan666@xxxxxxxxxxxxxxx 写道:
From: Li Nan <linan122@xxxxxxxxxx>
If we write a large number to md/bitmap_set_bits, md_bitmap_checkpage()
will return -EINVAL because "page >= bitmap->pages", but the return value
was not checked immediately in md_bitmap_get_counter() in order to set
*blocks value and slab-out-of-bounds occurs.
Return directly if err is -EINVAL.
Fixes: ef4256733506 ("md/bitmap: optimise scanning of empty bitmaps.")
Signed-off-by: Li Nan <linan122@xxxxxxxxxx>
This patch looks good to me, feel free to add：
Reviewed-by: Yu Kuai <yukuai3@xxxxxxxxxx>
By the way, I think it's better for bitmap_store() to return error
number if bitmap doesn't exist or setting dirty bits failed.
Thnaks,
Kuai
---
drivers/md/md-bitmap.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 920bb68156d2..0b41ef422da7 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -1388,6 +1388,8 @@ __acquires(bitmap->lock)
int err;
err = md_bitmap_checkpage(bitmap, page, create, 0);
+ if (err == -EINVAL)
+ return NULL;
if (bitmap->bp[page].hijacked ||
bitmap->bp[page].map == NULL)
