Re: [PATCH v2 12/25] selinux: add hooks for fscaps operations
From: Paul Moore <paul@paul-moore.com>
Date: 2024-02-21 23:38:44
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linux-doc, linux-fsdevel, linux-integrity, linux-unionfs, lkml, selinux
On Wed, Feb 21, 2024 at 4:25 PM Seth Forshee (DigitalOcean) [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Add hooks for set/get/remove fscaps operations which perform the same checks as the xattr hooks would have done for XATTR_NAME_CAPS. Signed-off-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org> --- security/selinux/hooks.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index a6bf90ace84c..da129a387b34 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c@@ -3367,6 +3367,29 @@ static int selinux_inode_removexattr(struct mnt_idmap *idmap, return -EACCES; } +static int selinux_inode_set_fscaps(struct mnt_idmap *idmap, + struct dentry *dentry, + const struct vfs_caps *caps, int flags) +{ + return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); +}
The selinux_inode_setxattr() code also has a cap_inode_setxattr() check which is missing here. Unless you are handling this somewhere else, I would expect the function above to look similar to selinux_inode_remove_fscaps(), but obviously tweaked for setting the fscaps and not removing them.
quoted hunk ↗ jump to hunk
+static int selinux_inode_get_fscaps(struct mnt_idmap *idmap, + struct dentry *dentry) +{ + return dentry_has_perm(current_cred(), dentry, FILE__GETATTR); +} + +static int selinux_inode_remove_fscaps(struct mnt_idmap *idmap, + struct dentry *dentry) +{ + int rc = cap_inode_removexattr(idmap, dentry, XATTR_NAME_CAPS); + if (rc) + return rc; + + return dentry_has_perm(current_cred(), dentry, FILE__SETATTR); +} + static int selinux_path_notify(const struct path *path, u64 mask, unsigned int obj_type) {@@ -7165,6 +7188,9 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = { LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl), LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl), LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl), + LSM_HOOK_INIT(inode_set_fscaps, selinux_inode_set_fscaps), + LSM_HOOK_INIT(inode_get_fscaps, selinux_inode_get_fscaps), + LSM_HOOK_INIT(inode_remove_fscaps, selinux_inode_remove_fscaps), LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), --2.43.0
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