This function never attempts to allocate memory, so returning -ENOMEM
looks weird to me. The reason of the failure is there is no more space
in the given kobj_uevent_env structure.
Let's change the error code to -ENOSPC.
This patch is safe since this function had never failed in reality.
The callers of this function put a fixed number of small strings into
the buffer.
The buffer is defined to be large enough:
#define UEVENT_NUM_ENVP 32 /* number of env pointers */
#define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */
As you see WARN() in the error paths, any failure of this function is
a software bug.
If such a case had ever happened before, you would have already seen
a noisy back-trace, then you would have increased UEVENT_NUM_ENVP or
UEVENT_BUFFER_SIZE.
Nobody has ever increased UEVENT_NUM_ENVP or UEVENT_BUFFER_SIZE since
their addition, that is, this structure is always large enough.
Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
---
Changes in v2:
- Rephrase the commit log. No code change.
lib/kobject_uevent.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 7998affa45d4..5ffd44bf4aad 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -647,7 +647,7 @@ EXPORT_SYMBOL_GPL(kobject_uevent);
* @env: environment buffer structure
* @format: printf format for the key=value pair
*
- * Returns 0 if environment variable was added successfully or -ENOMEM
+ * Returns 0 if environment variable was added successfully or -ENOSPC
* if no space was available.
*/
int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
@@ -657,7 +657,7 @@ int add_uevent_var(struct kobj_uevent_env *env, const char
*format, ...)
if (env->envp_idx >= ARRAY_SIZE(env->envp)) {
WARN(1, KERN_ERR "add_uevent_var: too many keys\n");
- return -ENOMEM;
+ return -ENOSPC;
}
va_start(args, format);
@@ -668,7 +668,7 @@ int add_uevent_var(struct kobj_uevent_env *env, const char
*format, ...)
if (len >= (sizeof(env->buf) - env->buflen)) {
WARN(1, KERN_ERR "add_uevent_var: buffer size too small\n");
- return -ENOMEM;
+ return -ENOSPC;
}
env->envp[env->envp_idx++] = &env->buf[env->buflen];
--
2.17.1
