[PATCH net-next] genetlink: fix error return code in genl_register_family()

[PATCH net-next] genetlink: fix error return code in genl_register_family()

[Wei Yongjun]

From: Wei Yongjun <weiyongjun1@huawei.com>

Fix to return error code -ENOMEM from the idr_alloc() error handling
case instead of 0, as done elsewhere in this function.

Fixes: 2ae0f17df1cd ("genetlink: use idr to track families")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
---
 net/netlink/genetlink.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index caf04d7..305730d 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -362,8 +362,10 @@ int genl_register_family(struct genl_family *family)
 
 	family->id = idr_alloc(&genl_fam_idr, family,
 			       start, end + 1, GFP_KERNEL);
-	if (!family->id)
+	if (!family->id) {
+		err = -ENOMEM;
 		goto errout_locked;
+	}
 
 	err = genl_validate_assign_mc_groups(family);
 	if (err)

Re: [PATCH net-next] genetlink: fix error return code in genl_register_family()

[David Miller]

From: Wei Yongjun <weiyj.lk@gmail.com>
Date: Mon, 31 Oct 2016 14:53:03 +0000

> From: Wei Yongjun <weiyongjun1@huawei.com>
> 
> Fix to return error code -ENOMEM from the idr_alloc() error handling
> case instead of 0, as done elsewhere in this function.
> 
> Fixes: 2ae0f17df1cd ("genetlink: use idr to track families")
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
 ...
> @@ -362,8 +362,10 @@ int genl_register_family(struct genl_family *family)
>  
>  	family->id = idr_alloc(&genl_fam_idr, family,
>  			       start, end + 1, GFP_KERNEL);
> -	if (!family->id)
> +	if (!family->id) {
> +		err = -ENOMEM;
>  		goto errout_locked;
> +	}
>  
>  	err = genl_validate_assign_mc_groups(family);
>  	if (err)

idr_alloc() returns negative error codes, not zero, on failure.

So we should return whatever idr_alloc() returns because it has
at least two error return cases (ENOSPC and ENOMEM).

[PATCH net-next v2] genetlink: fix error return code in genl_register_family()

[Wei Yongjun]

From: Wei Yongjun <weiyongjun1@huawei.com>

Fix to return a negative error code from the idr_alloc() error handling
case instead of 0, as done elsewhere in this function.

Also fix the return value check of idr_alloc() since idr_alloc return
negative errors on failure, not zero.

Fixes: 2ae0f17df1cd ("genetlink: use idr to track families")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
---
v1 -> v2: fix the return value check and return idr_alloc's err code
---
 net/netlink/genetlink.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index caf04d7..bbd3bff 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -362,8 +362,10 @@ int genl_register_family(struct genl_family *family)
 
 	family->id = idr_alloc(&genl_fam_idr, family,
 			       start, end + 1, GFP_KERNEL);
-	if (!family->id)
+	if (family->id < 0) {
+		err = family->id;
 		goto errout_locked;
+	}
 
 	err = genl_validate_assign_mc_groups(family);
 	if (err)

Re: [PATCH net-next v2] genetlink: fix error return code in genl_register_family()

[David Miller]

From: Wei Yongjun <weiyj.lk@gmail.com>
Date: Tue,  1 Nov 2016 14:45:52 +0000

> From: Wei Yongjun <weiyongjun1@huawei.com>
> 
> Fix to return a negative error code from the idr_alloc() error handling
> case instead of 0, as done elsewhere in this function.
> 
> Also fix the return value check of idr_alloc() since idr_alloc return
> negative errors on failure, not zero.
> 
> Fixes: 2ae0f17df1cd ("genetlink: use idr to track families")
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
> ---
> v1 -> v2: fix the return value check and return idr_alloc's err code

Applied, thanks.