On 4/20/21 10:35 PM, Santosh Sivaraj wrote:
Hi Santosh,
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.
Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Suggested-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
---
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 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;
Shouldn't there be a goto out_free_fdt if fdt_open_into fails?
You are likely looking at elf_64.c in the mainline branch. The patch I
have submitted is based on Rob's device-tree for-next branch. Please see
the link below:
https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git/tree/arch/powerpc/kexec/elf_64.c?h=for-next
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);
Can just use kfree here?
"fdt" is allocated through kvmalloc(). So it is freed using kvfree.
thanks,
-lakshmi
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;
}
--
2.31.0
