ACPI, APEI, Fix error path for memory allocation

In ERST debug/test support patch, a dynamic allocated buffer is
used. The may-failed memory allocation should be tried firstly before
free the previous buffer.

APEI resource management memory allocation related error path is fixed
too.

v2:

- Fix error messages for APEI resources management

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c
index 73fd0c7..4a904a4 100644 (file)
--- a/drivers/acpi/apei/apei-base.c
+++ b/drivers/acpi/apei/apei-base.c
@@ -445,11 +445,15 @@ EXPORT_SYMBOL_GPL(apei_resources_sub);
 int apei_resources_request(struct apei_resources *resources,
                           const char *desc)
 {
-       struct apei_res *res, *res_bak;
+       struct apei_res *res, *res_bak = NULL;
        struct resource *r;
+       int rc;
 
-       apei_resources_sub(resources, &apei_resources_all);
+       rc = apei_resources_sub(resources, &apei_resources_all);
+       if (rc)
+               return rc;
 
+       rc = -EINVAL;
        list_for_each_entry(res, &resources->iomem, list) {
                r = request_mem_region(res->start, res->end - res->start,
                                       desc);
@@ -475,7 +479,11 @@ int apei_resources_request(struct apei_resources *resources,
                }
        }
 
-       apei_resources_merge(&apei_resources_all, resources);
+       rc = apei_resources_merge(&apei_resources_all, resources);
+       if (rc) {
+               pr_err(APEI_PFX "Fail to merge resources!\n");
+               goto err_unmap_ioport;
+       }
 
        return 0;
 err_unmap_ioport:
@@ -491,12 +499,13 @@ err_unmap_iomem:
                        break;
                release_mem_region(res->start, res->end - res->start);
        }
-       return -EINVAL;
+       return rc;
 }
 EXPORT_SYMBOL_GPL(apei_resources_request);
 
 void apei_resources_release(struct apei_resources *resources)
 {
+       int rc;
        struct apei_res *res;
 
        list_for_each_entry(res, &resources->iomem, list)
@@ -504,7 +513,9 @@ void apei_resources_release(struct apei_resources *resources)
        list_for_each_entry(res, &resources->ioport, list)
                release_region(res->start, res->end - res->start);
 
-       apei_resources_sub(&apei_resources_all, resources);
+       rc = apei_resources_sub(&apei_resources_all, resources);
+       if (rc)
+               pr_err(APEI_PFX "Fail to sub resources!\n");
 }
 EXPORT_SYMBOL_GPL(apei_resources_release);
 

diff --git a/drivers/acpi/apei/erst-dbg.c b/drivers/acpi/apei/erst-dbg.c
index 5281ddd..8561cfe 100644 (file)
--- a/drivers/acpi/apei/erst-dbg.c
+++ b/drivers/acpi/apei/erst-dbg.c
@@ -111,11 +111,13 @@ retry:
                goto out;
        }
        if (len > erst_dbg_buf_len) {
-               kfree(erst_dbg_buf);
+               void *p;
                rc = -ENOMEM;
-               erst_dbg_buf = kmalloc(len, GFP_KERNEL);
-               if (!erst_dbg_buf)
+               p = kmalloc(len, GFP_KERNEL);
+               if (!p)
                        goto out;
+               kfree(erst_dbg_buf);
+               erst_dbg_buf = p;
                erst_dbg_buf_len = len;
                goto retry;
        }
@@ -150,11 +152,13 @@ static ssize_t erst_dbg_write(struct file *filp, const char __user *ubuf,
        if (mutex_lock_interruptible(&erst_dbg_mutex))
                return -EINTR;
        if (usize > erst_dbg_buf_len) {
-               kfree(erst_dbg_buf);
+               void *p;
                rc = -ENOMEM;
-               erst_dbg_buf = kmalloc(usize, GFP_KERNEL);
-               if (!erst_dbg_buf)
+               p = kmalloc(usize, GFP_KERNEL);
+               if (!p)
                        goto out;
+               kfree(erst_dbg_buf);
+               erst_dbg_buf = p;
                erst_dbg_buf_len = usize;
        }
        rc = copy_from_user(erst_dbg_buf, ubuf, usize);