[PATCH v5 3/4] scm: Convert put_cmsg() to scoped user access
From: Christophe Leroy <hidden>
Date: 2025-11-17 16:50:49
Also in:
linux-block, linux-fsdevel, linuxppc-dev, lkml
Subsystem:
networking [general], networking [sockets], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Linus Torvalds
Replace the open coded implementation with the scoped user access guards. No functional change intended. Signed-off-by: Christophe Leroy <redacted> --- v5: New --- net/core/scm.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-)
diff --git a/net/core/scm.c b/net/core/scm.c
index 66eaee783e8b..cd87f66671aa 100644
--- a/net/core/scm.c
+++ b/net/core/scm.c@@ -273,17 +273,13 @@ int put_cmsg(struct msghdr * msg, int level, int type, int len, void *data) check_object_size(data, cmlen - sizeof(*cm), true); - if (can_do_masked_user_access()) - cm = masked_user_access_begin(cm); - else if (!user_write_access_begin(cm, cmlen)) - goto efault; - - unsafe_put_user(cmlen, &cm->cmsg_len, efault_end); - unsafe_put_user(level, &cm->cmsg_level, efault_end); - unsafe_put_user(type, &cm->cmsg_type, efault_end); - unsafe_copy_to_user(CMSG_USER_DATA(cm), data, - cmlen - sizeof(*cm), efault_end); - user_write_access_end(); + scoped_user_write_access_size(cm, cmlen, efault) { + unsafe_put_user(cmlen, &cm->cmsg_len, efault); + unsafe_put_user(level, &cm->cmsg_level, efault); + unsafe_put_user(type, &cm->cmsg_type, efault); + unsafe_copy_to_user(CMSG_USER_DATA(cm), data, + cmlen - sizeof(*cm), efault); + } } else { struct cmsghdr *cm = msg->msg_control;
@@ -301,8 +297,6 @@ int put_cmsg(struct msghdr * msg, int level, int type, int len, void *data) msg->msg_controllen -= cmlen; return 0; -efault_end: - user_write_access_end(); efault: return -EFAULT; }
--
2.49.0