| From a0d83bf2878645681ddc248017069d17f3ced0e9 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 26 Apr 2021 18:13:45 -0400 |
| Subject: evm: fix writing <securityfs>/evm overflow |
| |
| From: Mimi Zohar <zohar@linux.ibm.com> |
| |
| [ Upstream commit 49219d9b8785ba712575c40e48ce0f7461254626 ] |
| |
| EVM_SETUP_COMPLETE is defined as 0x80000000, which is larger than INT_MAX. |
| The "-fno-strict-overflow" compiler option properly prevents signaling |
| EVM that the EVM policy setup is complete. Define and read an unsigned |
| int. |
| |
| Fixes: f00d79750712 ("EVM: Allow userspace to signal an RSA key has been loaded") |
| Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| security/integrity/evm/evm_secfs.c | 5 +++-- |
| 1 file changed, 3 insertions(+), 2 deletions(-) |
| |
| diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c |
| index a7042ae90b9e..bc10c945f3ed 100644 |
| --- a/security/integrity/evm/evm_secfs.c |
| +++ b/security/integrity/evm/evm_secfs.c |
| @@ -66,12 +66,13 @@ static ssize_t evm_read_key(struct file *filp, char __user *buf, |
| static ssize_t evm_write_key(struct file *file, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| - int i, ret; |
| + unsigned int i; |
| + int ret; |
| |
| if (!capable(CAP_SYS_ADMIN) || (evm_initialized & EVM_SETUP_COMPLETE)) |
| return -EPERM; |
| |
| - ret = kstrtoint_from_user(buf, count, 0, &i); |
| + ret = kstrtouint_from_user(buf, count, 0, &i); |
| |
| if (ret) |
| return ret; |
| -- |
| 2.30.2 |
| |
