From 0a16e24e34f28210f68195259456c73462518597 Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh@google.com>
Date: Wed, 4 Dec 2024 17:26:20 +0100
Subject: [PATCH] udmabuf: also check for F_SEAL_FUTURE_WRITE
When F_SEAL_FUTURE_WRITE was introduced, it was overlooked that udmabuf
must reject memfds with this flag, just like ones with F_SEAL_WRITE.
Fix it by adding F_SEAL_FUTURE_WRITE to SEALS_DENIED.
Fixes: ab3948f58ff8 ("mm/memfd: add an F_SEAL_FUTURE_WRITE seal to memfd")
Cc: stable@vger.kernel.org
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241204-udmabuf-fixes-v2-2-23887289de1c@google.com
---
drivers/dma-buf/udmabuf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
index c1d8c2766d6d3..b330b99fcc761 100644
--- a/drivers/dma-buf/udmabuf.c
+++ b/drivers/dma-buf/udmabuf.c
@@ -297,7 +297,7 @@ static const struct dma_buf_ops udmabuf_ops = {
};
#define SEALS_WANTED (F_SEAL_SHRINK)
-#define SEALS_DENIED (F_SEAL_WRITE)
+#define SEALS_DENIED (F_SEAL_WRITE|F_SEAL_FUTURE_WRITE)
static int check_memfd_seals(struct file *memfd)
{
--
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