bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 51 insertions, 0 deletions

diff --git a/arch/powerpc/boot/zImage.ps3.lds.S b/arch/powerpc/boot/zImage.ps3.lds.S
new file mode 100644
index 000000000..d0ffb4936
--- /dev/null
+++ b/arch/powerpc/boot/zImage.ps3.lds.S
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+OUTPUT_ARCH(powerpc:common)
+ENTRY(_zimage_start)
+EXTERN(_zimage_start)
+SECTIONS
+{
+  _vmlinux_start =  .;
+  .kernel:vmlinux.bin : { *(.kernel:vmlinux.bin) }
+  _vmlinux_end =  .;
+
+  . = ALIGN(8);
+  _dtb_start = .;
+  .kernel:dtb : { *(.kernel:dtb) }
+  _dtb_end = .;
+
+  . = ALIGN(4096);
+  _initrd_start =  .;
+  .kernel:initrd : { *(.kernel:initrd) }
+  _initrd_end =  .;
+
+  _start = .;
+  .text      :
+  {
+    *(.text)
+    *(.fixup)
+  }
+  _etext = .;
+  . = ALIGN(4096);
+  .data    :
+  {
+    *(.rodata*)
+    *(.data*)
+    *(.sdata*)
+    __got2_start = .;
+    *(.got2)
+    __got2_end = .;
+  }
+
+  . = ALIGN(4096);
+  _edata  =  .;
+
+  . = ALIGN(4096);
+  __bss_start = .;
+  .bss       :
+  {
+   *(.sbss)
+   *(.bss)
+  }
+  . = ALIGN(4096);
+  _end = . ;
+}