[PATCH][next] kexec_file: Assign array_size() to a variable

From: Gustavo A. R. Silva
Date: Fri Jul 10 2020 - 17:16:33 EST


Assign array_size() to variable _size_ and use it in both vzalloc()
and memcpy(). These sorts of multiplication factors need to be wrapped
in array_size().

This issue was found with the help of Coccinelle and, audited and fixed
manually.

Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
---
kernel/kexec_file.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 09cc78df53c6..4479d864aaf2 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -883,16 +883,16 @@ static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
unsigned long offset;
Elf_Shdr *sechdrs;
int i;
+ size_t size = array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum);

/*
* 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 = vzalloc(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, size);
pi->sechdrs = sechdrs;

offset = 0;
--
2.27.0