From 4a19f48bee09396b1eaef8995cb6b692d0e6465d Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 28 Nov 2022 14:24:39 -0600 Subject: [PATCH] of/kexec: Fix reading 32-bit "linux,initrd-{start,end}" values commit e553ad8d7957697385e81034bf76db3b2cb2cf27 upstream. "linux,initrd-start" and "linux,initrd-end" can be 32-bit values even on a 64-bit platform. Ideally, the size should be based on '#address-cells', but that has never been enforced in the kernel's FDT boot parsing code (early_init_dt_check_for_initrd()). Bootloader behavior is known to vary. For example, kexec always writes these as 64-bit. The result of incorrectly reading 32-bit values is most likely the reserved memory for the original initrd will still be reserved for the new kernel. The original arm64 equivalent of this code failed to release the initrd reserved memory in *all* cases. Use of_read_number() to mirror the early_init_dt_check_for_initrd() code. Fixes: b30be4dc733e ("of: Add a common kexec FDT setup function") Cc: stable@vger.kernel.org Reported-by: Peter Maydell Link: https://lore.kernel.org/r/20221128202440.1411895-1-robh@kernel.org Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman --- drivers/of/kexec.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c index 8f9dba1..52bb68f 100644 --- a/drivers/of/kexec.c +++ b/drivers/of/kexec.c @@ -284,7 +284,7 @@ void *of_kexec_alloc_and_setup_fdt(const struct kimage *image, const char *cmdline, size_t extra_fdt_size) { void *fdt; - int ret, chosen_node; + int ret, chosen_node, len; const void *prop; size_t fdt_size; @@ -327,19 +327,19 @@ void *of_kexec_alloc_and_setup_fdt(const struct kimage *image, goto out; /* Did we boot using an initrd? */ - prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL); + prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", &len); if (prop) { u64 tmp_start, tmp_end, tmp_size; - tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop)); + tmp_start = of_read_number(prop, len / 4); - prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL); + prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", &len); if (!prop) { ret = -EINVAL; goto out; } - tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop)); + tmp_end = of_read_number(prop, len / 4); /* * kexec reserves exact initrd size, while firmware may -- 2.7.4