xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

{compat_,}verify_iovec(): switch to generic copying of iovecs

Browse Source 
use {compat_,}rw_copy_check_uvector().  As the result, we are
guaranteed that all iovecs seen in ->msg_iov by ->sendmsg()
and ->recvmsg() will pass access_ok().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2014-11-09 22:33:45 -05:00
parent 666547ff59
commit 0844932009
3 changed files with 36 additions and 88 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
net/compat.c
View File

@@ -31,33 +31,6 @@
#include <asm/uaccess.h>
#include <net/compat.h>
static inline int iov_from_user_compat_to_kern(struct iovec *kiov,
struct compat_iovec __user *uiov32,
int niov)
{
int tot_len = 0;
while (niov > 0) {
compat_uptr_t buf;
compat_size_t len;
if (get_user(len, &uiov32->iov_len) ||
get_user(buf, &uiov32->iov_base))
return -EFAULT;
if (len > INT_MAX - tot_len)
len = INT_MAX - tot_len;
tot_len += len;
kiov->iov_base = compat_ptr(buf);
kiov->iov_len = (__kernel_size_t) len;
uiov32++;
kiov++;
niov--;
}
return tot_len;
}
int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
{
compat_uptr_t tmp1, tmp2, tmp3;
@@ -80,13 +53,15 @@ int get_compat_msghdr(struct msghdr *kmsg, struct compat_msghdr __user *umsg)
}
/* I've named the args so it is easy to tell whose space the pointers are in. */
int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *iov,
struct sockaddr_storage *kern_address, int mode)
{
int tot_len;
struct compat_iovec __user *p;
struct iovec *res;
int err;
if (kern_msg->msg_name && kern_msg->msg_namelen) {
if (mode == VERIFY_READ) {
if (mode == WRITE) {
int err = move_addr_to_kernel(kern_msg->msg_name,
kern_msg->msg_namelen,
kern_address);
@@ -99,13 +74,17 @@ int verify_compat_iovec(struct msghdr *kern_msg, struct iovec *kern_iov,
kern_msg->msg_namelen = 0;
}
tot_len = iov_from_user_compat_to_kern(kern_iov,
(struct compat_iovec __user *)kern_msg->msg_iov,
kern_msg->msg_iovlen);
if (tot_len >= 0)
kern_msg->msg_iov = kern_iov;
if (kern_msg->msg_iovlen > UIO_MAXIOV)
return -EMSGSIZE;
return tot_len;
p = (struct compat_iovec __user *)kern_msg->msg_iov;
err = compat_rw_copy_check_uvector(mode, p, kern_msg->msg_iovlen,
UIO_FASTIOV, iov, &res);
if (err >= 0)
kern_msg->msg_iov = res;
else if (res != iov)
kfree(res);
return err;
}
/* Bleech... */