This sets MS_POSIXACL only if ACL support is really enabled, instead
of always setting MS_POSIXACL if the NFS protocol version
theoretically supports ACL.
The code comment says "We will [apply the umask] ourselves", but that
happens in posix_acl_create() only if the kernel has POSIX ACL
support. Without it, posix_acl_create() is an empty dummy function.
So let's not pretend we will apply the umask if we can already know
that we will never.
This fixes a problem where the umask is always ignored in the NFS
client when compiled without CONFIG_FS_POSIX_ACL. This is a 4 year
old regression caused by commit 013cdf1088d723 which itself was not
completely wrong, but failed to consider all the side effects by
misdesigned VFS code.
Signed-off-by: Max Kellermann <[email protected]>
---
fs/nfs/super.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 29bacdc56f6a..fa9929723bfe 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2345,11 +2345,14 @@ void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
if (data && data->bsize)
sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
- if (server->nfs_client->rpc_ops->version != 2) {
+ if (NFS_SB(sb)->caps & NFS_CAP_ACLS) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
sb->s_flags |= SB_POSIXACL;
+ }
+
+ if (server->nfs_client->rpc_ops->version != 2) {
sb->s_time_gran = 1;
sb->s_export_op = &nfs_export_ops;
}
@@ -2375,7 +2378,7 @@ static void nfs_clone_super(struct super_block *sb,
sb->s_time_gran = 1;
sb->s_export_op = old_sb->s_export_op;
- if (server->nfs_client->rpc_ops->version != 2) {
+ if (NFS_SB(sb)->caps & NFS_CAP_ACLS) {
/* The VFS shouldn't apply the umask to mode bits. We will do
* so ourselves when necessary.
*/
On Tue, 2023-09-19 at 10:18 +0200, Max Kellermann wrote:
> This sets SB_POSIXACL only if ACL support is really enabled, instead
> of always setting SB_POSIXACL if the NFS protocol version
> theoretically supports ACL.
>
> The code comment says "We will [apply the umask] ourselves", but that
> happens in posix_acl_create() only if the kernel has POSIX ACL
> support. Without it, posix_acl_create() is an empty dummy function.
>
> So let's not pretend we will apply the umask if we can already know
> that we will never.
>
> This fixes a problem where the umask is always ignored in the NFS
> client when compiled without CONFIG_FS_POSIX_ACL. This is a 4 year
> old regression caused by commit 013cdf1088d723 which itself was not
> completely wrong, but failed to consider all the side effects by
> misdesigned VFS code.
>
A little more than 4 years now!
> Reviewed-by: J. Bruce Fields <[email protected]>
> Cc: [email protected]
> Signed-off-by: Max Kellermann <[email protected]>
> ---
> fs/nfs/super.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
> index 0d6473cb00cb..051986b422b0 100644
> --- a/fs/nfs/super.c
> +++ b/fs/nfs/super.c
> @@ -1064,14 +1064,19 @@ static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx)
> * The VFS shouldn't apply the umask to mode bits.
> * We will do so ourselves when necessary.
> */
> - sb->s_flags |= SB_POSIXACL;
> + if (NFS_SB(sb)->caps & NFS_CAP_ACLS) {
> + sb->s_flags |= SB_POSIXACL;
> + }
> +
nit: curly braces aren't needed here
> sb->s_time_gran = 1;
> sb->s_time_min = 0;
> sb->s_time_max = U32_MAX;
> sb->s_export_op = &nfs_export_ops;
> break;
> case 4:
> - sb->s_flags |= SB_POSIXACL;
> + if (NFS_SB(sb)->caps & NFS_CAP_ACLS) {
> + sb->s_flags |= SB_POSIXACL;
> + }
> sb->s_time_gran = 1;
> sb->s_time_min = S64_MIN;
> sb->s_time_max = S64_MAX;
(cc'ing Christian)
This patch may have a minor conflict with this patch:
https://lore.kernel.org/linux-nfs/[email protected]/
...but it seems like the right thing to do if POSIX ACLs are compiled
out.
Reviewed-by: Jeff Layton <[email protected]>