The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
Possible dependencies:
f0861f49bd94 ("x86/sgx: Add overflow check in sgx_validate_offset_length()")
dda03e2c331b ("x86/sgx: Create utility to validate user provided offset and length")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From f0861f49bd946ff94fce4f82509c45e167f63690 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Borys=20Pop=C5=82awski?= <borysp@xxxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 5 Oct 2022 00:59:03 +0200
Subject: [PATCH] x86/sgx: Add overflow check in sgx_validate_offset_length()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
sgx_validate_offset_length() function verifies "offset" and "length"
arguments provided by userspace, but was missing an overflow check on
their addition. Add it.
Fixes: c6d26d370767 ("x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES")
Signed-off-by: Borys Popławski <borysp@xxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v5.11+
Link: https://lore.kernel.org/r/0d91ac79-6d84-abed-5821-4dbe59fa1a38@xxxxxxxxxxxxxxxxxxxxxx
diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index ebe79d60619f..da8b8ea6b063 100644
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -356,6 +356,9 @@ static int sgx_validate_offset_length(struct sgx_encl *encl,
if (!length || !IS_ALIGNED(length, PAGE_SIZE))
return -EINVAL;
+ if (offset + length < offset)
+ return -EINVAL;
+
if (offset + length - PAGE_SIZE >= encl->size)
return -EINVAL;
