diff mbox series

NFSD: Annotate struct pnfs_block_deviceaddr with __counted_by()

Message ID 20240828214254.2407-2-thorsten.blum@toblux.com (mailing list archive)
State New
Headers show
Series NFSD: Annotate struct pnfs_block_deviceaddr with __counted_by() | expand

Commit Message

Thorsten Blum Aug. 28, 2024, 9:42 p.m. UTC
Add the __counted_by compiler attribute to the flexible array member
volumes to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.

Use struct_size() instead of manually calculating the number of bytes to
allocate for a pnfs_block_deviceaddr with a single volume.

Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
---
 fs/nfsd/blocklayout.c    | 6 ++----
 fs/nfsd/blocklayoutxdr.h | 2 +-
 2 files changed, 3 insertions(+), 5 deletions(-)

Comments

Jeff Layton Aug. 28, 2024, 10:09 p.m. UTC | #1
On Wed, 2024-08-28 at 23:42 +0200, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> volumes to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
> 
> Use struct_size() instead of manually calculating the number of bytes to
> allocate for a pnfs_block_deviceaddr with a single volume.
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
> ---
>  fs/nfsd/blocklayout.c    | 6 ++----
>  fs/nfsd/blocklayoutxdr.h | 2 +-
>  2 files changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
> index 3c040c81c77d..08a20e5bcf7f 100644
> --- a/fs/nfsd/blocklayout.c
> +++ b/fs/nfsd/blocklayout.c
> @@ -147,8 +147,7 @@ nfsd4_block_get_device_info_simple(struct super_block *sb,
>  	struct pnfs_block_deviceaddr *dev;
>  	struct pnfs_block_volume *b;
>  
> -	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
> -		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
> +	dev = kzalloc(struct_size(dev, volumes, 1), GFP_KERNEL);
>  	if (!dev)
>  		return -ENOMEM;
>  	gdp->gd_device = dev;
> @@ -255,8 +254,7 @@ nfsd4_block_get_device_info_scsi(struct super_block *sb,
>  	const struct pr_ops *ops;
>  	int ret;
>  
> -	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
> -		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
> +	dev = kzalloc(struct_size(dev, volumes, 1), GFP_KERNEL);
>  	if (!dev)
>  		return -ENOMEM;
>  	gdp->gd_device = dev;
> diff --git a/fs/nfsd/blocklayoutxdr.h b/fs/nfsd/blocklayoutxdr.h
> index b0361e8aa9a7..4e28ac8f1127 100644
> --- a/fs/nfsd/blocklayoutxdr.h
> +++ b/fs/nfsd/blocklayoutxdr.h
> @@ -47,7 +47,7 @@ struct pnfs_block_volume {
>  
>  struct pnfs_block_deviceaddr {
>  	u32				nr_volumes;
> -	struct pnfs_block_volume	volumes[];
> +	struct pnfs_block_volume	volumes[] __counted_by(nr_volumes);
>  };
>  
>  __be32 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,

Acked-by: Jeff Layton <jlayton@kernel.org>
Gustavo A. R. Silva Aug. 28, 2024, 11:58 p.m. UTC | #2
On 28/08/24 15:42, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> volumes to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
> 
> Use struct_size() instead of manually calculating the number of bytes to
> allocate for a pnfs_block_deviceaddr with a single volume.
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>

Looks good --`nr_volumes` is updated just before accessing `volumes[]`.

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks
--
Gustavo

> ---
>   fs/nfsd/blocklayout.c    | 6 ++----
>   fs/nfsd/blocklayoutxdr.h | 2 +-
>   2 files changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
> index 3c040c81c77d..08a20e5bcf7f 100644
> --- a/fs/nfsd/blocklayout.c
> +++ b/fs/nfsd/blocklayout.c
> @@ -147,8 +147,7 @@ nfsd4_block_get_device_info_simple(struct super_block *sb,
>   	struct pnfs_block_deviceaddr *dev;
>   	struct pnfs_block_volume *b;
>   
> -	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
> -		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
> +	dev = kzalloc(struct_size(dev, volumes, 1), GFP_KERNEL);
>   	if (!dev)
>   		return -ENOMEM;
>   	gdp->gd_device = dev;
> @@ -255,8 +254,7 @@ nfsd4_block_get_device_info_scsi(struct super_block *sb,
>   	const struct pr_ops *ops;
>   	int ret;
>   
> -	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
> -		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
> +	dev = kzalloc(struct_size(dev, volumes, 1), GFP_KERNEL);
>   	if (!dev)
>   		return -ENOMEM;
>   	gdp->gd_device = dev;
> diff --git a/fs/nfsd/blocklayoutxdr.h b/fs/nfsd/blocklayoutxdr.h
> index b0361e8aa9a7..4e28ac8f1127 100644
> --- a/fs/nfsd/blocklayoutxdr.h
> +++ b/fs/nfsd/blocklayoutxdr.h
> @@ -47,7 +47,7 @@ struct pnfs_block_volume {
>   
>   struct pnfs_block_deviceaddr {
>   	u32				nr_volumes;
> -	struct pnfs_block_volume	volumes[];
> +	struct pnfs_block_volume	volumes[] __counted_by(nr_volumes);
>   };
>   
>   __be32 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,
Chuck Lever III Aug. 29, 2024, 2:37 p.m. UTC | #3
On Wed, 28 Aug 2024 23:42:55 +0200, Thorsten Blum wrote:
> Add the __counted_by compiler attribute to the flexible array member
> volumes to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
> CONFIG_FORTIFY_SOURCE.
> 
> Use struct_size() instead of manually calculating the number of bytes to
> allocate for a pnfs_block_deviceaddr with a single volume.
> 
> [...]

Applied to nfsd-next for v6.12, thanks!

[1/1] NFSD: Annotate struct pnfs_block_deviceaddr with __counted_by()
      commit: 7dd2311b21ef121d0ce9f9b2e56d3e42b2534991
diff mbox series

Patch

diff --git a/fs/nfsd/blocklayout.c b/fs/nfsd/blocklayout.c
index 3c040c81c77d..08a20e5bcf7f 100644
--- a/fs/nfsd/blocklayout.c
+++ b/fs/nfsd/blocklayout.c
@@ -147,8 +147,7 @@  nfsd4_block_get_device_info_simple(struct super_block *sb,
 	struct pnfs_block_deviceaddr *dev;
 	struct pnfs_block_volume *b;
 
-	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
-		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
+	dev = kzalloc(struct_size(dev, volumes, 1), GFP_KERNEL);
 	if (!dev)
 		return -ENOMEM;
 	gdp->gd_device = dev;
@@ -255,8 +254,7 @@  nfsd4_block_get_device_info_scsi(struct super_block *sb,
 	const struct pr_ops *ops;
 	int ret;
 
-	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
-		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
+	dev = kzalloc(struct_size(dev, volumes, 1), GFP_KERNEL);
 	if (!dev)
 		return -ENOMEM;
 	gdp->gd_device = dev;
diff --git a/fs/nfsd/blocklayoutxdr.h b/fs/nfsd/blocklayoutxdr.h
index b0361e8aa9a7..4e28ac8f1127 100644
--- a/fs/nfsd/blocklayoutxdr.h
+++ b/fs/nfsd/blocklayoutxdr.h
@@ -47,7 +47,7 @@  struct pnfs_block_volume {
 
 struct pnfs_block_deviceaddr {
 	u32				nr_volumes;
-	struct pnfs_block_volume	volumes[];
+	struct pnfs_block_volume	volumes[] __counted_by(nr_volumes);
 };
 
 __be32 nfsd4_block_encode_getdeviceinfo(struct xdr_stream *xdr,