From b62d59e57437213c9ed34bf58495288fa23ffccc Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Mon, 26 Apr 2021 18:13:45 -0400 Subject: evm: fix writing /evm overflow [ 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 Signed-off-by: Sasha Levin --- security/integrity/evm/evm_secfs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'security') diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c index c175e2b659e4..5f0da41bccd0 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; -- cgit v1.2.3