1 files changed, 66 insertions, 19 deletions

diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c
index f9e4baa64b67..8f43575a4dd3 100644
--- a/arch/s390/kernel/machine_kexec_file.c
+++ b/arch/s390/kernel/machine_kexec_file.c
@@ -7,11 +7,14 @@
  * Author(s): Philipp Rudo <prudo@linux.vnet.ibm.com>
  */
 
+#define pr_fmt(fmt)	"kexec: " fmt
+
 #include <linux/elf.h>
 #include <linux/errno.h>
 #include <linux/kexec.h>
 #include <linux/module_signature.h>
 #include <linux/verification.h>
+#include <linux/vmalloc.h>
 #include <asm/boot_data.h>
 #include <asm/ipl.h>
 #include <asm/setup.h>
@@ -170,6 +173,7 @@ static int kexec_file_add_ipl_report(struct kimage *image,
 	struct kexec_buf buf;
 	unsigned long addr;
 	void *ptr, *end;
+	int ret;
 
 	buf.image = image;
 
@@ -199,9 +203,13 @@ static int kexec_file_add_ipl_report(struct kimage *image,
 		ptr += len;
 	}
 
+	ret = -ENOMEM;
 	buf.buffer = ipl_report_finish(data->report);
+	if (!buf.buffer)
+		goto out;
 	buf.bufsz = data->report->size;
 	buf.memsz = buf.bufsz;
+	image->arch.ipl_buf = buf.buffer;
 
 	data->memsz += buf.memsz;
 
@@ -209,14 +217,18 @@ static int kexec_file_add_ipl_report(struct kimage *image,
 		data->kernel_buf + offsetof(struct lowcore, ipl_parmblock_ptr);
 	*lc_ipl_parmblock_ptr = (__u32)buf.mem;
 
-	return kexec_add_buffer(&buf);
+	ret = kexec_add_buffer(&buf);
+out:
+	return ret;
 }
 
 void *kexec_file_add_components(struct kimage *image,
 				int (*add_kernel)(struct kimage *image,
 						  struct s390_load_data *data))
 {
+	unsigned long max_command_line_size = LEGACY_COMMAND_LINE_SIZE;
 	struct s390_load_data data = {0};
+	unsigned long minsize;
 	int ret;
 
 	data.report = ipl_report_init(&ipl_block);
@@ -227,10 +239,23 @@ void *kexec_file_add_components(struct kimage *image,
 	if (ret)
 		goto out;
 
-	if (image->cmdline_buf_len >= ARCH_COMMAND_LINE_SIZE) {
-		ret = -EINVAL;
+	ret = -EINVAL;
+	minsize = PARMAREA + offsetof(struct parmarea, command_line);
+	if (image->kernel_buf_len < minsize)
 		goto out;
-	}
+
+	if (data.parm->max_command_line_size)
+		max_command_line_size = data.parm->max_command_line_size;
+
+	if (minsize + max_command_line_size < minsize)
+		goto out;
+
+	if (image->kernel_buf_len < minsize + max_command_line_size)
+		goto out;
+
+	if (image->cmdline_buf_len >= max_command_line_size)
+		goto out;
+
 	memcpy(data.parm->command_line, image->cmdline_buf,
 	       image->cmdline_buf_len);
 
@@ -267,8 +292,16 @@ int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
 				     const Elf_Shdr *relsec,
 				     const Elf_Shdr *symtab)
 {
+	const char *strtab, *name, *shstrtab;
+	const Elf_Shdr *sechdrs;
 	Elf_Rela *relas;
 	int i, r_type;
+	int ret;
+
+	/* String & section header string table */
+	sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
+	strtab = (char *)pi->ehdr + sechdrs[symtab->sh_link].sh_offset;
+	shstrtab = (char *)pi->ehdr + sechdrs[pi->ehdr->e_shstrndx].sh_offset;
 
 	relas = (void *)pi->ehdr + relsec->sh_offset;
 
@@ -281,15 +314,27 @@ int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
 		sym = (void *)pi->ehdr + symtab->sh_offset;
 		sym += ELF64_R_SYM(relas[i].r_info);
 
-		if (sym->st_shndx == SHN_UNDEF)
+		if (sym->st_name)
+			name = strtab + sym->st_name;
+		else
+			name = shstrtab + sechdrs[sym->st_shndx].sh_name;
+
+		if (sym->st_shndx == SHN_UNDEF) {
+			pr_err("Undefined symbol: %s\n", name);
 			return -ENOEXEC;
+		}
 
-		if (sym->st_shndx == SHN_COMMON)
+		if (sym->st_shndx == SHN_COMMON) {
+			pr_err("symbol '%s' in common section\n", name);
 			return -ENOEXEC;
+		}
 
 		if (sym->st_shndx >= pi->ehdr->e_shnum &&
-		    sym->st_shndx != SHN_ABS)
+		    sym->st_shndx != SHN_ABS) {
+			pr_err("Invalid section %d for symbol %s\n",
+			       sym->st_shndx, name);
 			return -ENOEXEC;
+		}
 
 		loc = pi->purgatory_buf;
 		loc += section->sh_offset;
@@ -303,21 +348,23 @@ int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
 		addr = section->sh_addr + relas[i].r_offset;
 
 		r_type = ELF64_R_TYPE(relas[i].r_info);
-		arch_kexec_do_relocs(r_type, loc, val, addr);
+
+		if (r_type == R_390_PLT32DBL)
+			r_type = R_390_PC32DBL;
+
+		ret = arch_kexec_do_relocs(r_type, loc, val, addr);
+		if (ret) {
+			pr_err("Unknown rela relocation: %d\n", r_type);
+			return -ENOEXEC;
+		}
 	}
 	return 0;
 }
 
-int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
-				  unsigned long buf_len)
+int arch_kimage_file_post_load_cleanup(struct kimage *image)
 {
-	/* A kernel must be at least large enough to contain head.S. During
-	 * load memory in head.S will be accessed, e.g. to register the next
-	 * command line. If the next kernel were smaller the current kernel
-	 * will panic at load.
-	 */
-	if (buf_len < HEAD_END)
-		return -ENOEXEC;
-
-	return kexec_image_probe_default(image, buf, buf_len);
+	vfree(image->arch.ipl_buf);
+	image->arch.ipl_buf = NULL;
+
+	return kexec_image_post_load_cleanup_default(image);
 }