Re: [PATCH v2 1/2] powerpc: Free fdt on error in elf64_load()
From: Lakshmi Ramasubramanian <hidden>
Date: 2021-04-23 17:34:28
Also in:
linux-devicetree, oe-kbuild-all
On 4/21/21 9:36 AM, Lakshmi Ramasubramanian wrote: Hi Dan,
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. Reported-by: kernel test robot <redacted> Reported-by: Dan Carpenter <redacted> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Lakshmi Ramasubramanian <redacted> --- arch/powerpc/kexec/elf_64.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-)
Please review this patch and Patch 2/2. thanks, -lakshmi
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c index 5a569bb51349..02662e72c53d 100644 --- a/arch/powerpc/kexec/elf_64.c +++ b/arch/powerpc/kexec/elf_64.c@@ -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; }