6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Yao Zi ziyao@disroot.org
commit 70a2365e18affc5ebdaab1ca6a0b3c4f3aac2ee8 upstream.
In init_cpu_fullname(), a constant pointer to "model" property is retrieved. It's later modified by the strsep() function, which is illegal and corrupts kernel's FDT copy. This is shown by dmesg,
OF: fdt: not creating '/sys/firmware/fdt': CRC check failed
Create a mutable copy of the model property and do in-place operations on the mutable copy instead. loongson_sysconf.cpuname lives across the kernel lifetime, thus manually releasing isn't necessary.
Also move the of_node_put() call for the root node after the usage of its property, since of_node_put() decreases the reference counter thus usage after the call is unsafe.
Cc: stable@vger.kernel.org Fixes: 44a01f1f726a ("LoongArch: Parsing CPU-related information from DTS") Reviewed-by: Jiaxun Yang jiaxun.yang@flygoat.com Signed-off-by: Yao Zi ziyao@disroot.org Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/loongarch/kernel/env.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
--- a/arch/loongarch/kernel/env.c +++ b/arch/loongarch/kernel/env.c @@ -39,16 +39,19 @@ void __init init_environ(void)
static int __init init_cpu_fullname(void) { - struct device_node *root; int cpu, ret; - char *model; + char *cpuname; + const char *model; + struct device_node *root;
/* Parsing cpuname from DTS model property */ root = of_find_node_by_path("/"); - ret = of_property_read_string(root, "model", (const char **)&model); + ret = of_property_read_string(root, "model", &model); + if (ret == 0) { + cpuname = kstrdup(model, GFP_KERNEL); + loongson_sysconf.cpuname = strsep(&cpuname, " "); + } of_node_put(root); - if (ret == 0) - loongson_sysconf.cpuname = strsep(&model, " ");
if (loongson_sysconf.cpuname && !strncmp(loongson_sysconf.cpuname, "Loongson", 8)) { for (cpu = 0; cpu < NR_CPUS; cpu++)