On 17. 12. 24, 18:08, Greg Kroah-Hartman wrote:
6.12-stable review patch. If anyone has any objections, please let me know.
From: Juergen Gross jgross@suse.com
commit 0ef8047b737d7480a5d4c46d956e97c190f13050 upstream.
Add static_call_update_early() for updating static-call targets in very early boot.
This will be needed for support of Xen guest type specific hypercall functions.
This is part of XSA-466 / CVE-2024-53241.
Reported-by: Andrew Cooper andrew.cooper3@citrix.com Signed-off-by: Juergen Gross jgross@suse.com Co-developed-by: Peter Zijlstra peterz@infradead.org Co-developed-by: Josh Poimboeuf jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
arch/x86/include/asm/static_call.h | 15 +++++++++++++++ arch/x86/include/asm/sync_core.h | 6 +++--- arch/x86/kernel/static_call.c | 9 +++++++++ include/linux/compiler.h | 37 ++++++++++++++++++++++++++----------- include/linux/static_call.h | 1 + kernel/static_call_inline.c | 2 +- 6 files changed, 55 insertions(+), 15 deletions(-)
--- a/arch/x86/include/asm/static_call.h +++ b/arch/x86/include/asm/static_call.h @@ -65,4 +65,19 @@ extern bool __static_call_fixup(void *tramp, u8 op, void *dest); +extern void __static_call_update_early(void *tramp, void *func);
+#define static_call_update_early(name, _func) \ +({ \
- typeof(&STATIC_CALL_TRAMP(name)) __F = (_func); \
- if (static_call_initialized) { \
__static_call_update(&STATIC_CALL_KEY(name), \STATIC_CALL_TRAMP_ADDR(name), __F);\- } else { \
WRITE_ONCE(STATIC_CALL_KEY(name).func, _func); \__static_call_update_early(STATIC_CALL_TRAMP_ADDR(name),\__F); \- } \
+})
...
--- a/kernel/static_call_inline.c +++ b/kernel/static_call_inline.c @@ -15,7 +15,7 @@ extern struct static_call_site __start_s extern struct static_call_tramp_key __start_static_call_tramp_key[], __stop_static_call_tramp_key[]; -static int static_call_initialized; +int static_call_initialized;
This breaks the build on i386:
ld: arch/x86/xen/enlighten.o: in function `__xen_hypercall_setfunc': enlighten.c:(.noinstr.text+0x2a): undefined reference to `static_call_initialized' ld: enlighten.c:(.noinstr.text+0x62): undefined reference to `static_call_initialized' ld: arch/x86/kernel/static_call.o: in function `__static_call_update_early': static_call.c:(.noinstr.text+0x15): undefined reference to `static_call_initialized'
kernel/static_call_inline.c containing this `static_call_initialized` is not built there as: HAVE_STATIC_CALL_INLINE=n -> HAVE_OBJTOOL=n -> X86_64=n
This is broken in upstream too.
thanks,