mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-12-27 10:01:39 -05:00
Code Issues Packages Projects Releases Wiki Activity

scm: Convert put_cmsg() to scoped user access

Browse Source 
Replace the open coded implementation with the scoped user access guard.

That also corrects the imbalance between masked_user_access_begin() and
user_write_access_end(), which would affect PowerPC when it gains masked
user access support.

No functional change intended.

[ tglx: Amend change log ]

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/793219313f641eda09a892d06768d2837246bf9f.1763396724.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy
2025-11-17 17:43:43 +01:00
committed by Thomas Gleixner
parent 803abedbd5
commit 1c204914bc
1 changed files with 7 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
net/core/scm.c
View File

@@ -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;
}