From: Lakshmi Ramasubramanian nramas@linux.microsoft.com
mainline inclusion from mainline-v5.13-rc1 commit a45dd984dea9baa22b15fb692fe870ab5670a4a0 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I53YU3
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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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: 3c985d31ad66 ("powerpc: Use common of_kexec_alloc_and_setup_fdt()") Reported-by: kernel test robot lkp@intel.com Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Lakshmi Ramasubramanian nramas@linux.microsoft.com Signed-off-by: Rob Herring robh@kernel.org Link: https://lore.kernel.org/r/20210421163610.23775-1-nramas@linux.microsoft.com Signed-off-by: Lin Yujun linyujun809@huawei.com Reviewed-by: Zhang Jianhua chris.zjh@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- arch/powerpc/kexec/elf_64.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c index ed284be2e0f7..ee292bd2edf2 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; }