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From:   Christophe JAILLET <christophe.jaillet@wanadoo.fr>
To:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
        Eric Biederman <ebiederm@xmission.com>,
        Kees Cook <keescook@chromium.org>
Cc:     linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org
Subject: [PATCH 1/2] binfmt: Use struct_size()
Date:   Sun, 28 May 2023 18:20:24 +0200
Message-Id: <53150beae5dc04dac513dba391a2e4ae8696a7f3.1685290790.git.christophe.jaillet@wanadoo.fr>
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Use struct_size() instead of hand-writing it. It is less verbose, more
robust and more informative.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
Compile tested on arm
---
 fs/binfmt_elf_fdpic.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index d76ad3d4f676..237ce388d06d 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -748,7 +748,6 @@ static int elf_fdpic_map_file(struct elf_fdpic_params *params,
 	struct elf32_phdr *phdr;
 	unsigned long load_addr, stop;
 	unsigned nloads, tmp;
-	size_t size;
 	int loop, ret;
 
 	/* allocate a load map table */
@@ -760,8 +759,7 @@ static int elf_fdpic_map_file(struct elf_fdpic_params *params,
 	if (nloads == 0)
 		return -ELIBBAD;
 
-	size = sizeof(*loadmap) + nloads * sizeof(*seg);
-	loadmap = kzalloc(size, GFP_KERNEL);
+	loadmap = kzalloc(struct_size(loadmap, segs, nloads), GFP_KERNEL);
 	if (!loadmap)
 		return -ENOMEM;
 
-- 
2.34.1