[PATCHES] sysacls: fix FreeBSD developer build and HPUX POSIX ACL support
Jeremy Allison
jra at samba.org
Wed Dec 20 23:19:21 UTC 2017
On Wed, Dec 20, 2017 at 10:50:59PM +0200, Uri Simchoni via samba-technical wrote:
> Hi,
>
> The attach patches fix FreeBSD developer build for sysacls module
> (mode_t is 16 bits and the internal representation of the ACL entry is
> 32 bits). They also fix a bug of POSIX ACL support on hpux and possibly
> other big-endian platforms where mode_t is also 16 bits (on Linux mode_t
> is 32 bits).
>
> This is a simpler fix that's been proposed by Volker in response to my
> previous fix which also simplified the interface, but consisted of a
> larger patch set.
>
> I have confirmation on the existence of the bug in hpux, but not on the
> fix. However much time has passed without being able to confirm this, so
> I thought I'd go ahead and submit this to the list.
>
> Please review and maybe push :)
OK, I must be being dumb but I don't understand the fix, sorry :-(.
In librpc/idl/smb_acl.idl we have:
typedef struct {
smb_acl_tag_t a_type;
[switch_is(a_type)] smb_acl_entry_info info;
mode_t a_perm;
} smb_acl_entry;
so a_perm is explicitly defined as a mode_t. On Linux this
then gets mapped to a uint32_t, so in the pidl generated file
bin/default/librpc/gen_ndr/smb_acl.h we have:
struct smb_acl_entry {
enum smb_acl_tag_t a_type;
union smb_acl_entry_info info;/* [switch_is(a_type)] */
uint32_t a_perm;
};
I'm assuming on FreeBSD this would be:
struct smb_acl_entry {
enum smb_acl_tag_t a_type;
union smb_acl_entry_info info;/* [switch_is(a_type)] */
uint16_t a_perm;
};
Correct ?
Now in source3/lib/sysacls.c we have:
int sys_acl_get_permset(SMB_ACL_ENTRY_T entry_d, SMB_ACL_PERMSET_T *permset_p)
{
*permset_p = &entry_d->a_perm;
return 0;
}
So SMB_ACL_PERMSET_T should be a pointer to a mode_t, which will get mapped
to a pointer of the correct size. If you make SMB_ACL_PERMSET_T a pointer
to a uint32_t, then on FreeBSD isn't it going to be pointing to an element
of the wrong size ?
Can you explain why this fix works (sorry for being dumb) ?
Jeremy.
> From 61eb0695b22b3bc384066c801995e7d45b0178dc Mon Sep 17 00:00:00 2001
> From: Uri Simchoni <uri at samba.org>
> Date: Tue, 5 Dec 2017 20:49:03 +0200
> Subject: [PATCH 1/2] pysmbd: fix use of sysacl API
>
> Fix pysmbd to use the sysacl (POSIX ACL support) as intended, and
> not assume too much about the inner structure and implementation
> of the permissions in the sysacl API.
>
> This will allow the inner structure to change in a following commit.
>
> BUG: https://bugzilla.samba.org/show_bug.cgi?id=13176
>
> Signed-off-by: Uri Simchoni <uri at samba.org>
> ---
> source3/smbd/pysmbd.c | 43 ++++++++++++++++++++++++++++++++++++++-----
> 1 file changed, 38 insertions(+), 5 deletions(-)
>
> diff --git a/source3/smbd/pysmbd.c b/source3/smbd/pysmbd.c
> index 63fc5d6..be30b86 100644
> --- a/source3/smbd/pysmbd.c
> +++ b/source3/smbd/pysmbd.c
> @@ -234,6 +234,39 @@ static NTSTATUS get_nt_acl_conn(TALLOC_CTX *mem_ctx,
> return status;
> }
>
> +static int set_acl_entry_perms(SMB_ACL_ENTRY_T entry, mode_t perm_mask)
> +{
> + SMB_ACL_PERMSET_T perms = NULL;
> +
> + if (sys_acl_get_permset(entry, &perms) != 0) {
> + return -1;
> + }
> +
> + if (sys_acl_clear_perms(perms) != 0) {
> + return -1;
> + }
> +
> + if ((perm_mask & SMB_ACL_READ) != 0 &&
> + sys_acl_add_perm(perms, SMB_ACL_READ) != 0) {
> + return -1;
> + }
> +
> + if ((perm_mask & SMB_ACL_WRITE) != 0 &&
> + sys_acl_add_perm(perms, SMB_ACL_WRITE) != 0) {
> + return -1;
> + }
> +
> + if ((perm_mask & SMB_ACL_EXECUTE) != 0 &&
> + sys_acl_add_perm(perms, SMB_ACL_EXECUTE) != 0) {
> + return -1;
> + }
> +
> + if (sys_acl_set_permset(entry, perms) != 0) {
> + return -1;
> + }
> +
> + return 0;
> +}
>
> static SMB_ACL_T make_simple_acl(gid_t gid, mode_t chmod_mode)
> {
> @@ -261,7 +294,7 @@ static SMB_ACL_T make_simple_acl(gid_t gid, mode_t chmod_mode)
> return NULL;
> }
>
> - if (sys_acl_set_permset(entry, &mode_user) != 0) {
> + if (set_acl_entry_perms(entry, mode_user) != 0) {
> TALLOC_FREE(frame);
> return NULL;
> }
> @@ -276,7 +309,7 @@ static SMB_ACL_T make_simple_acl(gid_t gid, mode_t chmod_mode)
> return NULL;
> }
>
> - if (sys_acl_set_permset(entry, &mode_group) != 0) {
> + if (set_acl_entry_perms(entry, mode_group) != 0) {
> TALLOC_FREE(frame);
> return NULL;
> }
> @@ -291,7 +324,7 @@ static SMB_ACL_T make_simple_acl(gid_t gid, mode_t chmod_mode)
> return NULL;
> }
>
> - if (sys_acl_set_permset(entry, &mode_other) != 0) {
> + if (set_acl_entry_perms(entry, mode_other) != 0) {
> TALLOC_FREE(frame);
> return NULL;
> }
> @@ -312,7 +345,7 @@ static SMB_ACL_T make_simple_acl(gid_t gid, mode_t chmod_mode)
> return NULL;
> }
>
> - if (sys_acl_set_permset(entry, &mode_group) != 0) {
> + if (set_acl_entry_perms(entry, mode_group) != 0) {
> TALLOC_FREE(frame);
> return NULL;
> }
> @@ -328,7 +361,7 @@ static SMB_ACL_T make_simple_acl(gid_t gid, mode_t chmod_mode)
> return NULL;
> }
>
> - if (sys_acl_set_permset(entry, &mode) != 0) {
> + if (set_acl_entry_perms(entry, mode) != 0) {
> TALLOC_FREE(frame);
> return NULL;
> }
> --
> 2.9.5
>
>
> From 5e8d89d6f9a3bf84fef35f3e4584ff6844b00b38 Mon Sep 17 00:00:00 2001
> From: Uri Simchoni <uri at samba.org>
> Date: Tue, 5 Dec 2017 20:56:49 +0200
> Subject: [PATCH 2/2] sysacls: change datatypes to 32 bits
>
> The SMB_ACL_PERMSET_T and SMB_ACL_PERM_T were defined as
> mode_t, which is 16-bits on some (non-Linux) systems. That
> created a bug on big-endian systems. Changing to 32 bits fixes
> that.
>
> BUG: https://bugzilla.samba.org/show_bug.cgi?id=13176
>
> Signed-off-by: Uri Simchoni <uri at samba.org>
> ---
> source3/include/smb_acls.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/source3/include/smb_acls.h b/source3/include/smb_acls.h
> index 73b67af..74fab6c 100644
> --- a/source3/include/smb_acls.h
> +++ b/source3/include/smb_acls.h
> @@ -27,8 +27,8 @@ struct files_struct;
> struct smb_filename;
>
> typedef int SMB_ACL_TYPE_T;
> -typedef mode_t *SMB_ACL_PERMSET_T;
> -typedef mode_t SMB_ACL_PERM_T;
> +typedef uint32_t *SMB_ACL_PERMSET_T;
> +typedef uint32_t SMB_ACL_PERM_T;
>
> typedef enum smb_acl_tag_t SMB_ACL_TAG_T;
> typedef struct smb_acl_t *SMB_ACL_T;
> --
> 2.9.5
>
More information about the samba-technical
mailing list