From: Borys Popławski <borysp@xxxxxxxxxxxxxxxxxxxxxx>
[ Upstream commit f0861f49bd946ff94fce4f82509c45e167f63690 ]
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
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/kernel/cpu/sgx/ioctl.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index a66795e0b685..217777c029ee 100644
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -386,6 +386,9 @@ 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;
--
2.35.1
