Commit a45dd984 authored by Lakshmi Ramasubramanian's avatar Lakshmi Ramasubramanian Committed by Rob Herring
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powerpc: Free fdt on error in elf64_load() 



There are a few "goto out;" statements before the local variable "fdt"
is initialized through the call to of_kexec_alloc_and_setup_fdt() in
elf64_load().  This will result in an uninitialized "fdt" being passed
to kvfree() in this function if there is an error before the call to
of_kexec_alloc_and_setup_fdt().

If there is any error after fdt is allocated, but before it is
saved in the arch specific kimage struct, free the fdt.

Fixes: 3c985d31 ("powerpc: Use common of_kexec_alloc_and_setup_fdt()")
Reported-by: default avatarkernel test robot <lkp@intel.com>
Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: default avatarLakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210421163610.23775-1-nramas@linux.microsoft.com
parent aed4349c

arch/powerpc/kexec/elf_64.c

+6 −10
Original line number Diff line number Diff line
@@ -114,7 +114,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, 
	ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr,

				  initrd_len, cmdline);

	if (ret)

		goto out;

		goto out_free_fdt;



	fdt_pack(fdt);
@@ -125,7 +125,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, 
	kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;

	ret = kexec_add_buffer(&kbuf);

	if (ret)

		goto out;

		goto out_free_fdt;



	/* FDT will be freed in arch_kimage_file_post_load_cleanup */

	image->arch.fdt = fdt;
@@ -140,18 +140,14 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, 
	if (ret)

		pr_err("Error setting up the purgatory.\n");



	goto out;



out_free_fdt:

	kvfree(fdt);

out:

	kfree(modified_cmdline);

	kexec_free_elf_info(&elf_info);



	/*

	 * Once FDT buffer has been successfully passed to kexec_add_buffer(),

	 * the FDT buffer address is saved in image->arch.fdt. In that case,

	 * the memory cannot be freed here in case of any other error.

	 */

	if (ret && !image->arch.fdt)

		kvfree(fdt);



	return ret ? ERR_PTR(ret) : NULL;

}