[PATCH 1/2] fs/ceph/mds_client: pass cred pointer to ceph_mds_auth_match()

[PATCH 1/2] fs/ceph/mds_client: pass cred pointer to ceph_mds_auth_match()

[Max Kellermann]

This eliminates a redundant get_current_cred() call, because
ceph_mds_check_access() has already obtained this pointer.

As a side effect, this also fixes a reference leak in
ceph_mds_auth_match(): by omitting the get_current_cred() call, no
additional cred reference is taken.

Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
Cc: stable@vger.kernel.org
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/mds_client.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 6baec1387f7d..e8a5994de8b6 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -5615,9 +5615,9 @@ void send_flush_mdlog(struct ceph_mds_session *s)
 
 static int ceph_mds_auth_match(struct ceph_mds_client *mdsc,
 			       struct ceph_mds_cap_auth *auth,
+			       const struct cred *cred,
 			       char *tpath)
 {
-	const struct cred *cred = get_current_cred();
 	u32 caller_uid = from_kuid(&init_user_ns, cred->fsuid);
 	u32 caller_gid = from_kgid(&init_user_ns, cred->fsgid);
 	struct ceph_client *cl = mdsc->fsc->client;
@@ -5740,7 +5740,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
 	for (i = 0; i < mdsc->s_cap_auths_num; i++) {
 		struct ceph_mds_cap_auth *s = &mdsc->s_cap_auths[i];
 
-		err = ceph_mds_auth_match(mdsc, s, tpath);
+		err = ceph_mds_auth_match(mdsc, s, cred, tpath);
 		if (err < 0) {
 			return err;
 		} else if (err > 0) {
-- 
2.45.2

[PATCH 2/2] fs/ceph/mds_client: fix cred leak in ceph_mds_check_access()

[Max Kellermann]

get_current_cred() increments the reference counter, but the
put_cred() call was missing.

Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
Cc: stable@vger.kernel.org
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/mds_client.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index e8a5994de8b6..35d83c8c2874 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -5742,6 +5742,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
 
 		err = ceph_mds_auth_match(mdsc, s, cred, tpath);
 		if (err < 0) {
+			put_cred(cred);
 			return err;
 		} else if (err > 0) {
 			/* always follow the last auth caps' permision */
@@ -5757,6 +5758,8 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
 		}
 	}
 
+	put_cred(cred);
+
 	doutc(cl, "root_squash_perms %d, rw_perms_s %p\n", root_squash_perms,
 	      rw_perms_s);
 	if (root_squash_perms && rw_perms_s == NULL) {
-- 
2.45.2

Re: [PATCH 2/2] fs/ceph/mds_client: fix cred leak in ceph_mds_check_access()

[Xiubo Li]

On 11/23/24 15:21, Max Kellermann wrote:
> get_current_cred() increments the reference counter, but the
> put_cred() call was missing.
>
> Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
> Cc: stable@vger.kernel.org
> Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> ---
>   fs/ceph/mds_client.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
> index e8a5994de8b6..35d83c8c2874 100644
> --- a/fs/ceph/mds_client.c
> +++ b/fs/ceph/mds_client.c
> @@ -5742,6 +5742,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
>   
>   		err = ceph_mds_auth_match(mdsc, s, cred, tpath);
>   		if (err < 0) {
> +			put_cred(cred);
>   			return err;
>   		} else if (err > 0) {
>   			/* always follow the last auth caps' permision */
> @@ -5757,6 +5758,8 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
>   		}
>   	}
>   
> +	put_cred(cred);
> +
>   	doutc(cl, "root_squash_perms %d, rw_perms_s %p\n", root_squash_perms,
>   	      rw_perms_s);
>   	if (root_squash_perms && rw_perms_s == NULL) {

Good catch.

Reviewed-by: Xiubo Li <xiubli@redhat.com>

Re: [PATCH 2/2] fs/ceph/mds_client: fix cred leak in ceph_mds_check_access()

[Ilya Dryomov]

On Mon, Nov 25, 2024 at 1:53 AM Xiubo Li <xiubli@redhat.com> wrote:
>
>
> On 11/23/24 15:21, Max Kellermann wrote:
> > get_current_cred() increments the reference counter, but the
> > put_cred() call was missing.
> >
> > Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> > ---
> >   fs/ceph/mds_client.c | 3 +++
> >   1 file changed, 3 insertions(+)
> >
> > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
> > index e8a5994de8b6..35d83c8c2874 100644
> > --- a/fs/ceph/mds_client.c
> > +++ b/fs/ceph/mds_client.c
> > @@ -5742,6 +5742,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
> >
> >               err = ceph_mds_auth_match(mdsc, s, cred, tpath);
> >               if (err < 0) {
> > +                     put_cred(cred);
> >                       return err;
> >               } else if (err > 0) {
> >                       /* always follow the last auth caps' permision */
> > @@ -5757,6 +5758,8 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
> >               }
> >       }
> >
> > +     put_cred(cred);
> > +
> >       doutc(cl, "root_squash_perms %d, rw_perms_s %p\n", root_squash_perms,
> >             rw_perms_s);
> >       if (root_squash_perms && rw_perms_s == NULL) {
>
> Good catch.
>
> Reviewed-by: Xiubo Li <xiubli@redhat.com>

Applied.

Thanks,

                Ilya

Re: [PATCH 1/2] fs/ceph/mds_client: pass cred pointer to ceph_mds_auth_match()

[Xiubo Li]

On 11/23/24 15:21, Max Kellermann wrote:
> This eliminates a redundant get_current_cred() call, because
> ceph_mds_check_access() has already obtained this pointer.
>
> As a side effect, this also fixes a reference leak in
> ceph_mds_auth_match(): by omitting the get_current_cred() call, no
> additional cred reference is taken.
>
> Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
> Cc: stable@vger.kernel.org
> Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> ---
>   fs/ceph/mds_client.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
> index 6baec1387f7d..e8a5994de8b6 100644
> --- a/fs/ceph/mds_client.c
> +++ b/fs/ceph/mds_client.c
> @@ -5615,9 +5615,9 @@ void send_flush_mdlog(struct ceph_mds_session *s)
>   
>   static int ceph_mds_auth_match(struct ceph_mds_client *mdsc,
>   			       struct ceph_mds_cap_auth *auth,
> +			       const struct cred *cred,
>   			       char *tpath)
>   {
> -	const struct cred *cred = get_current_cred();
>   	u32 caller_uid = from_kuid(&init_user_ns, cred->fsuid);
>   	u32 caller_gid = from_kgid(&init_user_ns, cred->fsgid);
>   	struct ceph_client *cl = mdsc->fsc->client;
> @@ -5740,7 +5740,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
>   	for (i = 0; i < mdsc->s_cap_auths_num; i++) {
>   		struct ceph_mds_cap_auth *s = &mdsc->s_cap_auths[i];
>   
> -		err = ceph_mds_auth_match(mdsc, s, tpath);
> +		err = ceph_mds_auth_match(mdsc, s, cred, tpath);
>   		if (err < 0) {
>   			return err;
>   		} else if (err > 0) {

Good catch.

Reviewed-by: Xiubo Li <xiubli@redhat.com>

Re: [PATCH 1/2] fs/ceph/mds_client: pass cred pointer to ceph_mds_auth_match()

[Ilya Dryomov]

On Mon, Nov 25, 2024 at 1:53 AM Xiubo Li <xiubli@redhat.com> wrote:
>
>
> On 11/23/24 15:21, Max Kellermann wrote:
> > This eliminates a redundant get_current_cred() call, because
> > ceph_mds_check_access() has already obtained this pointer.
> >
> > As a side effect, this also fixes a reference leak in
> > ceph_mds_auth_match(): by omitting the get_current_cred() call, no
> > additional cred reference is taken.
> >
> > Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> > ---
> >   fs/ceph/mds_client.c | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
> > index 6baec1387f7d..e8a5994de8b6 100644
> > --- a/fs/ceph/mds_client.c
> > +++ b/fs/ceph/mds_client.c
> > @@ -5615,9 +5615,9 @@ void send_flush_mdlog(struct ceph_mds_session *s)
> >
> >   static int ceph_mds_auth_match(struct ceph_mds_client *mdsc,
> >                              struct ceph_mds_cap_auth *auth,
> > +                            const struct cred *cred,
> >                              char *tpath)
> >   {
> > -     const struct cred *cred = get_current_cred();
> >       u32 caller_uid = from_kuid(&init_user_ns, cred->fsuid);
> >       u32 caller_gid = from_kgid(&init_user_ns, cred->fsgid);
> >       struct ceph_client *cl = mdsc->fsc->client;
> > @@ -5740,7 +5740,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
> >       for (i = 0; i < mdsc->s_cap_auths_num; i++) {
> >               struct ceph_mds_cap_auth *s = &mdsc->s_cap_auths[i];
> >
> > -             err = ceph_mds_auth_match(mdsc, s, tpath);
> > +             err = ceph_mds_auth_match(mdsc, s, cred, tpath);
> >               if (err < 0) {
> >                       return err;
> >               } else if (err > 0) {
>
> Good catch.
>
> Reviewed-by: Xiubo Li <xiubli@redhat.com>

Applied.

Thanks,

                Ilya