From 0e71666b8b9e21e4cb5d805219eb5ed7c5617ca3 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Thu, 11 Jul 2019 20:52:58 -0700 Subject: ocfs2/dlm: use struct_size() helper One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct dlm_migratable_lockres { ... struct dlm_migratable_lock ml[0]; // 16 bytes each, begins at byte 112 }; Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. So, replace the following form: sizeof(struct dlm_migratable_lockres) + (mres->num_locks * sizeof(struct dlm_migratable_lock)) with: struct_size(mres, ml, mres->num_locks) Notice that, in this case, variable sz is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Link: http://lkml.kernel.org/r/20190605204926.GA24467@embeddedor Signed-off-by: Gustavo A. R. Silva Reviewed-by: Joseph Qi Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Changwei Ge Cc: Gang He Cc: Jun Piao Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ocfs2/dlm/dlmrecovery.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c index e22d6a115220..064ce5bbc3f6 100644 --- a/fs/ocfs2/dlm/dlmrecovery.c +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -1109,7 +1109,7 @@ static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, { u64 mig_cookie = be64_to_cpu(mres->mig_cookie); int mres_total_locks = be32_to_cpu(mres->total_locks); - int sz, ret = 0, status = 0; + int ret = 0, status = 0; u8 orig_flags = mres->flags, orig_master = mres->master; @@ -1117,9 +1117,6 @@ static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, if (!mres->num_locks) return 0; - sz = sizeof(struct dlm_migratable_lockres) + - (mres->num_locks * sizeof(struct dlm_migratable_lock)); - /* add an all-done flag if we reached the last lock */ orig_flags = mres->flags; BUG_ON(total_locks > mres_total_locks); @@ -1133,7 +1130,8 @@ static int dlm_send_mig_lockres_msg(struct dlm_ctxt *dlm, /* send it */ ret = o2net_send_message(DLM_MIG_LOCKRES_MSG, dlm->key, mres, - sz, send_to, &status); + struct_size(mres, ml, mres->num_locks), + send_to, &status); if (ret < 0) { /* XXX: negative status is not handled. * this will end up killing this node. */ -- cgit v1.2.3-58-ga151