kexec: avoid calculating array size twice

Avoid calculating array size twice in kexec_purgatory_setup_sechdrs().
Once using array_size(), and once open-coded.

Flagged by Coccinelle:

  .../kexec_file.c:881:8-25: WARNING: array_size is already used (line 877) to compute the same size

No functional change intended.
Compile tested only.

Link: https://lkml.kernel.org/r/20230525-kexec-array_size-v1-1-8b4bf4f7500a@kernel.org
Signed-off-by: Simon Horman <horms@kernel.org>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index f989f5f..3f56776 100644 (file)
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -867,6 +867,7 @@ static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
 {
        unsigned long bss_addr;
        unsigned long offset;
+       size_t sechdrs_size;
        Elf_Shdr *sechdrs;
        int i;
 
@@ -874,11 +875,11 @@ static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
         * The section headers in kexec_purgatory are read-only. In order to
         * have them modifiable make a temporary copy.
         */
-       sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum));
+       sechdrs_size = array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum);
+       sechdrs = vzalloc(sechdrs_size);
        if (!sechdrs)
                return -ENOMEM;
-       memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff,
-              pi->ehdr->e_shnum * sizeof(Elf_Shdr));
+       memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff, sechdrs_size);
        pi->sechdrs = sechdrs;
 
        offset = 0;