From 8c359d0ff88a09f802b77f60d22797a04ef72afa Mon Sep 17 00:00:00 2001 From: Schspa Shi Date: Wed, 29 Jun 2022 10:29:48 +0800 Subject: [PATCH] vfio: Clear the caps->buf to NULL after free On buffer resize failure, vfio_info_cap_add() will free the buffer, report zero for the size, and return -ENOMEM. As additional hardening, also clear the buffer pointer to prevent any chance of a double free. Signed-off-by: Schspa Shi Reviewed-by: Cornelia Huck Link: https://lore.kernel.org/r/20220629022948.55608-1-schspa@gmail.com Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 61e71c1154be6..a0fb93866f611 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1812,6 +1812,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, buf = krealloc(caps->buf, caps->size + size, GFP_KERNEL); if (!buf) { kfree(caps->buf); + caps->buf = NULL; caps->size = 0; return ERR_PTR(-ENOMEM); } -- 2.39.5