set_fs() fixes for 5.10

set_fs() is being deprecated in 5.10 on account of some security
problems (https://lwn.net/Articles/832121) and thus causes build
problems. This replaces set_fs() with kernel_read() and kernel_write()
to r&w to kernel's address space.

(build & runtime tested on 5.10.0-rc4)
This commit is contained in:
bhavay grover 2020-11-22 15:58:17 -05:00
parent c48292877c
commit e2873668ab

View File

@ -1545,25 +1545,19 @@ static int writeFile(struct file *fp,char *buf,int len)
* @return Linux specific error code
*/
static int isFileReadable(char *path)
{
{
struct file *fp;
int ret = 0;
mm_segment_t oldfs;
char buf;
fp=filp_open(path, O_RDONLY, 0);
fp=filp_open(path, O_RDONLY, 0);
if(IS_ERR(fp)) {
ret = PTR_ERR(fp);
}
else {
oldfs = get_fs(); set_fs(KERNEL_DS);
if(1!=readFile(fp, &buf, 1))
ret = PTR_ERR(fp);
set_fs(oldfs);
filp_close(fp,NULL);
}
ret = kernel_read(fp, &buf, 1, NULL);
closeFile(fp);
}
return ret;
}
@ -1584,13 +1578,11 @@ static int retriveFromFile(char *path, u8* buf, u32 sz)
if( 0 == (ret=openFile(&fp,path, O_RDONLY, 0)) ){
DBG_871X("%s openFile path:%s fp=%p\n",__FUNCTION__, path ,fp);
oldfs = get_fs(); set_fs(KERNEL_DS);
ret=readFile(fp, buf, sz);
set_fs(oldfs);
ret = kernel_read(fp, buf, sz, NULL);
closeFile(fp);
DBG_871X("%s readFile, ret:%d\n",__FUNCTION__, ret);
} else {
DBG_871X("%s openFile path:%s Fail, ret:%d\n",__FUNCTION__, path, ret);
}
@ -1613,21 +1605,19 @@ static int storeToFile(char *path, u8* buf, u32 sz)
int ret =0;
mm_segment_t oldfs;
struct file *fp;
if(path && buf) {
if( 0 == (ret=openFile(&fp, path, O_CREAT|O_WRONLY, 0666)) ) {
DBG_871X("%s openFile path:%s fp=%p\n",__FUNCTION__, path ,fp);
oldfs = get_fs(); set_fs(KERNEL_DS);
ret=writeFile(fp, buf, sz);
set_fs(oldfs);
ret = kernel_write(fp, buf, sz, NULL);
closeFile(fp);
DBG_871X("%s writeFile, ret:%d\n",__FUNCTION__, ret);
} else {
DBG_871X("%s openFile path:%s Fail, ret:%d\n",__FUNCTION__, path, ret);
}
}
} else {
DBG_871X("%s NULL pointer\n",__FUNCTION__);
ret = -EINVAL;