Please apply this config bugfix from Serge Hallyn.
The following changes since commit bbf5c979011a099af5dc76498918ed7df445635b:
Linux 5.9 (2020-10-11 14:15:50 -0700)
are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git tags/fixes-v5.10a
for you to fetch changes up to ed9b25d1970a4787ac6a39c2091e63b127ecbfc1:
[SECURITY] fix namespaced fscaps when !CONFIG_SECURITY (2020-12-04 16:24:11 -0800)
----------------------------------------------------------------
Fix namespaced fscaps when !CONFIG_SECURITY from Serge Hallyn.
----------------------------------------------------------------
Serge Hallyn (1):
[SECURITY] fix namespaced fscaps when !CONFIG_SECURITY
include/linux/security.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
commit ed9b25d1970a4787ac6a39c2091e63b127ecbfc1
Author: Serge Hallyn <[email protected]>
Date: Sun Nov 15 21:55:31 2020 -0600
[SECURITY] fix namespaced fscaps when !CONFIG_SECURITY
Namespaced file capabilities were introduced in 8db6c34f1dbc .
When userspace reads an xattr for a namespaced capability, a
virtualized representation of it is returned if the caller is
in a user namespace owned by the capability's owning rootid.
The function which performs this virtualization was not hooked
up if CONFIG_SECURITY=n. Therefore in that case the original
xattr was shown instead of the virtualized one.
To test this using libcap-bin (*1),
$ v=$(mktemp)
$ unshare -Ur setcap cap_sys_admin-eip $v
$ unshare -Ur setcap -v cap_sys_admin-eip $v
/tmp/tmp.lSiIFRvt8Y: OK
"setcap -v" verifies the values instead of setting them, and
will check whether the rootid value is set. Therefore, with
this bug un-fixed, and with CONFIG_SECURITY=n, setcap -v will
fail:
$ v=$(mktemp)
$ unshare -Ur setcap cap_sys_admin=eip $v
$ unshare -Ur setcap -v cap_sys_admin=eip $v
nsowner[got=1000, want=0],/tmp/tmp.HHDiOOl9fY differs in []
Fix this bug by calling cap_inode_getsecurity() in
security_inode_getsecurity() instead of returning
-EOPNOTSUPP, when CONFIG_SECURITY=n.
*1 - note, if libcap is too old for getcap to have the '-n'
option, then use verify-caps instead.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209689
Cc: Herv? Guillemet <[email protected]>
Acked-by: Casey Schaufler <[email protected]>
Signed-off-by: Serge Hallyn <[email protected]>
Signed-off-by: Andrew G. Morgan <[email protected]>
Signed-off-by: James Morris <[email protected]>
diff --git a/include/linux/security.h b/include/linux/security.h
index 0a0a03b36a3b..2befc0a25eb3 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -864,7 +864,7 @@ static inline int security_inode_killpriv(struct dentry *dentry)
static inline int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
{
- return -EOPNOTSUPP;
+ return cap_inode_getsecurity(inode, name, buffer, alloc);
}
static inline int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags)