[v2,04/19] xen/sysctl: wrap around XEN_SYSCTL_readconsole

Commit Message

Penny, Zheng March 26, 2025, 5:50 a.m. UTC

The following functions is to deal with XEN_SYSCTL_readconsole sub-op, and
shall be wrapped:
- xsm_readconsole
- read_console_ring

Signed-off-by: Penny Zheng <[e-mail]>
---
v1 -> v2:
- remove redundant dummy handle
- add transient #ifdef in sysctl.c for correct compilation
---
 xen/common/sysctl.c        | 2 ++
 xen/drivers/char/console.c | 2 ++
 xen/include/xsm/xsm.h      | 4 ++++
 xen/xsm/dummy.c            | 2 +-
 xen/xsm/flask/hooks.c      | 4 ++--
 5 files changed, 11 insertions(+), 3 deletions(-)

Comments

Stefano Stabellini March 29, 2025, 12:07 a.m. UTC | #1

On Wed, 26 Mar 2025, Penny Zheng wrote:
> The following functions is to deal with XEN_SYSCTL_readconsole sub-op, and
> shall be wrapped:
> - xsm_readconsole
> - read_console_ring
> 
> Signed-off-by: Penny Zheng <[e-mail]>

Reviewed-by: Stefano Stabellini <[e-mail]>

Patch

diff --git a/xen/common/sysctl.c b/xen/common/sysctl.c
index c2d99ae12e..dfc87a2846 100644
--- a/xen/common/sysctl.c
+++ b/xen/common/sysctl.c
@@ -58,6 +58,7 @@  long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
 
     switch ( op->cmd )
     {
+#ifdef CONFIG_SYSCTL
     case XEN_SYSCTL_readconsole:
         ret = xsm_readconsole(XSM_HOOK, op->u.readconsole.clear);
         if ( ret )
@@ -66,6 +67,7 @@  long do_sysctl(XEN_GUEST_HANDLE_PARAM(xen_sysctl_t) u_sysctl)
         ret = read_console_ring(&op->u.readconsole);
         break;
 
+#endif /* CONFIG_SYSCTL */
     case XEN_SYSCTL_tbuf_op:
         ret = tb_control(&op->u.tbuf_op);
         break;
diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
index c3150fbdb7..64f7e146a7 100644
--- a/xen/drivers/char/console.c
+++ b/xen/drivers/char/console.c
@@ -336,6 +336,7 @@  static void conring_puts(const char *str, size_t len)
         conringc = conringp - conring_size;
 }
 
+#ifdef CONFIG_SYSCTL
 long read_console_ring(struct xen_sysctl_readconsole *op)
 {
     XEN_GUEST_HANDLE_PARAM(char) str;
@@ -378,6 +379,7 @@  long read_console_ring(struct xen_sysctl_readconsole *op)
 
     return 0;
 }
+#endif /* CONFIG_SYSCTL */
 
 
 /*
diff --git a/xen/include/xsm/xsm.h b/xen/include/xsm/xsm.h
index 22e2429f52..042a99449f 100644
--- a/xen/include/xsm/xsm.h
+++ b/xen/include/xsm/xsm.h
@@ -270,7 +270,11 @@  static inline int xsm_sysctl(xsm_default_t def, int cmd)
 
 static inline int xsm_readconsole(xsm_default_t def, uint32_t clear)
 {
+#ifdef CONFIG_SYSCTL
     return alternative_call(xsm_ops.readconsole, clear);
+#else
+    return -EOPNOTSUPP;
+#endif
 }
 
 static inline int xsm_evtchn_unbound(
diff --git a/xen/xsm/dummy.c b/xen/xsm/dummy.c
index 93a0665ecc..cd0e844fcf 100644
--- a/xen/xsm/dummy.c
+++ b/xen/xsm/dummy.c
@@ -24,8 +24,8 @@  static const struct xsm_ops __initconst_cf_clobber dummy_ops = {
     .domctl                        = xsm_domctl,
 #ifdef CONFIG_SYSCTL
     .sysctl                        = xsm_sysctl,
-#endif
     .readconsole                   = xsm_readconsole,
+#endif
 
     .evtchn_unbound                = xsm_evtchn_unbound,
     .evtchn_interdomain            = xsm_evtchn_interdomain,
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index befe9336ee..df7e10775b 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -934,7 +934,6 @@  static int cf_check flask_sysctl(int cmd)
         return avc_unknown_permission("sysctl", cmd);
     }
 }
-#endif
 
 static int cf_check flask_readconsole(uint32_t clear)
 {
@@ -945,6 +944,7 @@  static int cf_check flask_readconsole(uint32_t clear)
 
     return domain_has_xen(current->domain, perms);
 }
+#endif /* CONFIG_SYSCTL */
 
 static inline uint32_t resource_to_perm(uint8_t access)
 {
@@ -1888,8 +1888,8 @@  static const struct xsm_ops __initconst_cf_clobber flask_ops = {
     .domctl = flask_domctl,
 #ifdef CONFIG_SYSCTL
     .sysctl = flask_sysctl,
-#endif
     .readconsole = flask_readconsole,
+#endif
 
     .evtchn_unbound = flask_evtchn_unbound,
     .evtchn_interdomain = flask_evtchn_interdomain,