UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

RDS: Make sure cmsgs aren't used in improper ways 

It hasn't cropped up in the field, but this code ensures it is
impossible to issue operations that pass an rdma cookie (DEST, MAP)
in the same sendmsg call that's actually initiating rdma or atomic
ops.

Disallowing this perverse-but-technically-allowed usage makes silent
RDMA heuristics slightly easier.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
This commit is contained in:
Andy Grover 2010-04-13 12:00:35 -07:00
parent 2c3a5f9abb
commit aa0a4ef4ac
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
net/rds/send.c
View File

@ -846,6 +846,7 @@ static int rds_rm_size(struct msghdr *msg, int data_len)
{ {
struct cmsghdr *cmsg; struct cmsghdr *cmsg;
int size = 0; int size = 0;
int cmsg_groups = 0;
int retval; int retval;
for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
@ -857,19 +858,23 @@ static int rds_rm_size(struct msghdr *msg, int data_len)
switch (cmsg->cmsg_type) { switch (cmsg->cmsg_type) {
case RDS_CMSG_RDMA_ARGS: case RDS_CMSG_RDMA_ARGS:
cmsg_groups |= 1;
retval = rds_rdma_extra_size(CMSG_DATA(cmsg)); retval = rds_rdma_extra_size(CMSG_DATA(cmsg));
if (retval < 0) if (retval < 0)
return retval; return retval;
size += retval; size += retval;
break; break;
case RDS_CMSG_RDMA_DEST: case RDS_CMSG_RDMA_DEST:
case RDS_CMSG_RDMA_MAP: case RDS_CMSG_RDMA_MAP:
cmsg_groups |= 2;
/* these are valid but do no add any size */ /* these are valid but do no add any size */
break; break;
case RDS_CMSG_ATOMIC_CSWP: case RDS_CMSG_ATOMIC_CSWP:
case RDS_CMSG_ATOMIC_FADD: case RDS_CMSG_ATOMIC_FADD:
cmsg_groups |= 1;
size += sizeof(struct scatterlist); size += sizeof(struct scatterlist);
break; break;
@ -881,6 +886,10 @@ static int rds_rm_size(struct msghdr *msg, int data_len)
size += ceil(data_len, PAGE_SIZE) * sizeof(struct scatterlist); size += ceil(data_len, PAGE_SIZE) * sizeof(struct scatterlist);
/* Ensure (DEST, MAP) are never used with (ARGS, ATOMIC) */
if (cmsg_groups == 3)
return -EINVAL;
return size; return size;
} }