Re: [PATCH v2 2/3] powerpc/kexec_file: Fix null-ptr-def in extra size calculation
From: Sourabh Jain <hidden>
Date: 2026-07-29 04:01:52
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On 29/07/26 06:59, Jinjie Ruan wrote:
A static Sashiko AI review identified a potential NULL pointer dereference in kexec_extra_fdt_size_ppc64(). On platforms without any reserved memory regions, get_reserved_memory_ranges() can return 0 while leaving 'rmem' unallocated as NULL. Passing it directly leads to a kernel panic when evaluating 'rmem->nr_ranges'.
Yes that is possible, so it is worth adding NULL check for rmem. Feel free to add: Reviewed-by: Sourabh Jain <redacted>
quoted hunk ↗ jump to hunk
Add a NULL check for 'rmem' to prevent this crash. Cc: Sourabh Jain <redacted> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: stable@vger.kernel.org Fixes: 0d3ff067331e ("powerpc/kexec_file: fix extra size calculation for kexec FDT") Signed-off-by: Jinjie Ruan <redacted> --- arch/powerpc/kexec/file_load_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c index 8c72e12ea44e..6075b1c88511 100644 --- a/arch/powerpc/kexec/file_load_64.c +++ b/arch/powerpc/kexec/file_load_64.c@@ -664,7 +664,7 @@ unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image, struct crash_mem * extra_size += (cpu_nodes - boot_cpu_node_count) * cpu_node_size(); /* Consider extra space for reserved memory ranges if any */ - if (rmem->nr_ranges > 0) + if (rmem && rmem->nr_ranges > 0) extra_size += sizeof(struct fdt_reserve_entry) * rmem->nr_ranges; return extra_size + kdump_extra_fdt_size_ppc64(image, cpu_nodes);