[xen staging] x86/pmstat: correct get_cpufreq_para()'s error return value

[patchbot@xxxxxxx]

commit 855337ca4947508ffca23393e291c54b5307cc9a
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Thu Mar 27 12:22:06 2025 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Thu Mar 27 12:22:06 2025 +0100

    x86/pmstat: correct get_cpufreq_para()'s error return value
    
    copy_to_guest() returns the number of bytes not copied; that's not what
    the function should return to its caller though. Convert to returning
    -EFAULT instead.
    
    Fixes: 7542c4ff00f2 ("Add user PM control interface")
    Reported-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 xen/drivers/acpi/pmstat.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/xen/drivers/acpi/pmstat.c b/xen/drivers/acpi/pmstat.c
index aae94529ab..c51b9ca358 100644
--- a/xen/drivers/acpi/pmstat.c
+++ b/xen/drivers/acpi/pmstat.c
@@ -230,12 +230,12 @@ static int get_cpufreq_para(struct xen_sysctl_pm_op *op)
 
     for ( i = 0; i < op->u.get_para.freq_num; i++ )
         data[i] = pmpt->perf.states[i].core_frequency * 1000;
-    ret = copy_to_guest(op->u.get_para.scaling_available_frequencies,
-                        data, op->u.get_para.freq_num) ?: ret;
+    ret += copy_to_guest(op->u.get_para.scaling_available_frequencies,
+                         data, op->u.get_para.freq_num);
 
     xfree(data);
     if ( ret )
-        return ret;
+        return -EFAULT;
 
     op->u.get_para.cpuinfo_cur_freq =
         cpufreq_driver.get ? alternative_call(cpufreq_driver.get, op->cpuid)
@@ -272,7 +272,7 @@ static int get_cpufreq_para(struct xen_sysctl_pm_op *op)
                             gov_num * CPUFREQ_NAME_LEN);
         xfree(scaling_available_governors);
         if ( ret )
-            return ret;
+            return -EFAULT;
 
         op->u.get_para.u.s.scaling_cur_freq = policy->cur;
         op->u.get_para.u.s.scaling_max_freq = policy->max;
--
generated by git-patchbot for /home/xen/git/xen.git#staging