Subject: Coverity: emulator_leave_smm(): Error handling issues

From: coverity-bot <[email-masked]>
Date: Thu, 1 Dec 2022 08:25:50 -0800

Hello!

This is an experimental semi-automated report about issues detected by
Coverity from a scan of next-20221201 as part of the linux-next scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan

You're getting this email because you were associated with the identified
lines of code (noted below) that were touched by commits:

  Wed Nov 9 12:31:18 2022 -0500
    1d0da94cdafe ("KVM: x86: do not go through ctxt->ops when emulating rsm")

Coverity reported the following:

*** CID 1527763:  Error handling issues  (CHECKED_RETURN)
arch/x86/kvm/smm.c:631 in emulator_leave_smm()
625     		cr4 = kvm_read_cr4(vcpu);
626     		if (cr4 & X86_CR4_PAE)
627     			kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PAE);
628
629     		/* And finally go back to 32-bit mode.  */
630     		efer = 0;
vvv     CID 1527763:  Error handling issues  (CHECKED_RETURN)
vvv     Calling "kvm_set_msr" without checking return value (as is done elsewhere 5 out of 6 times).
631     		kvm_set_msr(vcpu, MSR_EFER, efer);
632     	}
633     #endif
634
635     	/*
636     	 * Give leave_smm() a chance to make ISA-specific changes to the vCPU

If this is a false positive, please let us know so we can mark it as
such, or teach the Coverity rules to be smarter. If not, please make
sure fixes get into linux-next. :) For patches fixing this, please
include these lines (but double-check the "Fixes" first):

Reported-by: coverity-bot <[email-masked]>
Addresses-Coverity-ID: 1527763 ("Error handling issues")
Fixes: 1d0da94cdafe ("KVM: x86: do not go through ctxt->ops when emulating rsm")

Thanks for your attention!

-- 
Coverity-bot