From: Christian Göttsche cgzones@googlemail.com

stable inclusion from stable-v6.6.26 commit 477ed6789eb9f3f4d3568bb977f90c863c12724e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9QG73 CVE: CVE-2024-35904

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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commit 37801a36b4d68892ce807264f784d818f8d0d39b upstream.

In case kern_mount() fails and returns an error pointer return in the error branch instead of continuing and dereferencing the error pointer.

While on it drop the never read static variable selinuxfs_mount.

Cc: stable@vger.kernel.org Fixes: 0619f0f5e36f ("selinux: wrap selinuxfs state") Signed-off-by: Christian Göttsche cgzones@googlemail.com Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

Conflicts: security/selinux/selinuxfs.c [commit cd2bb4cb0996 db478cd60d55 was not merged, but it only adjust the attr of selinuxfs_mount, finally we delete it, so it does not affect the patch] Signed-off-by: Felix Fu fuzhen5@huawei.com --- security/selinux/selinuxfs.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index d893c2280f59..b45fb2924476 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -2205,7 +2205,6 @@ static struct file_system_type sel_fs_type = { .kill_sb = sel_kill_sb, };

-struct vfsmount *selinuxfs_mount; struct path selinux_null;

static int __init init_sel_fs(void) @@ -2227,18 +2226,21 @@ static int __init init_sel_fs(void) return err; }

- selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type); - if (IS_ERR(selinuxfs_mount)) { + selinux_null.mnt = kern_mount(&sel_fs_type); + if (IS_ERR(selinux_null.mnt)) { pr_err("selinuxfs: could not mount!\n"); - err = PTR_ERR(selinuxfs_mount); - selinuxfs_mount = NULL; + err = PTR_ERR(selinux_null.mnt); + selinux_null.mnt = NULL; + return err; } + selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root, &null_name); if (IS_ERR(selinux_null.dentry)) { pr_err("selinuxfs: could not lookup null!\n"); err = PTR_ERR(selinux_null.dentry); selinux_null.dentry = NULL; + return err; }

return err;