The patch titled
Subject: ipc: separate msg allocation from userspace copy
has been added to the -mm tree. Its filename is
ipc-separate-msg-allocation-from-userspace-copy.patch
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------------------------------------------------------
From: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
Subject: ipc: separate msg allocation from userspace copy
Separating msg allocation enables single-block vmalloc
allocation instead.
Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
Acked-by: Stanislav Kinsbursky <skinsbursky@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
ipc/msgutil.c | 52 +++++++++++++++++++++++++++++++++++-------------
1 file changed, 38 insertions(+), 14 deletions(-)
diff -puN ipc/msgutil.c~ipc-separate-msg-allocation-from-userspace-copy ipc/msgutil.c
--- a/ipc/msgutil.c~ipc-separate-msg-allocation-from-userspace-copy
+++ a/ipc/msgutil.c
@@ -44,21 +44,54 @@ struct msg_msgseg {
#define DATALEN_MSG (int)(PAGE_SIZE-sizeof(struct msg_msg))
#define DATALEN_SEG (int)(PAGE_SIZE-sizeof(struct msg_msgseg))
-struct msg_msg *load_msg(const void __user *src, int len)
+
+static struct msg_msg *alloc_msg(int len)
{
struct msg_msg *msg;
struct msg_msgseg **pseg;
- int err;
int alen;
alen = min(len, DATALEN_MSG);
msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL);
if (msg == NULL)
- return ERR_PTR(-ENOMEM);
+ return NULL;
msg->next = NULL;
msg->security = NULL;
+ len -= alen;
+ pseg = &msg->next;
+ while (len > 0) {
+ struct msg_msgseg *seg;
+ alen = min(len, DATALEN_SEG);
+ seg = kmalloc(sizeof(*seg) + alen, GFP_KERNEL);
+ if (seg == NULL)
+ goto out_err;
+ *pseg = seg;
+ seg->next = NULL;
+ pseg = &seg->next;
+ len -= alen;
+ }
+
+ return msg;
+
+out_err:
+ free_msg(msg);
+ return NULL;
+}
+
+struct msg_msg *load_msg(const void __user *src, int len)
+{
+ struct msg_msg *msg;
+ struct msg_msgseg *seg;
+ int err;
+ int alen;
+
+ msg = alloc_msg(len);
+ if (msg == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ alen = min(len, DATALEN_MSG);
if (copy_from_user(msg + 1, src, alen)) {
err = -EFAULT;
goto out_err;
@@ -66,23 +99,14 @@ struct msg_msg *load_msg(const void __us
len -= alen;
src = ((char __user *)src) + alen;
- pseg = &msg->next;
+ seg = msg->next;
while (len > 0) {
- struct msg_msgseg *seg;
alen = min(len, DATALEN_SEG);
- seg = kmalloc(sizeof(*seg) + alen,
- GFP_KERNEL);
- if (seg == NULL) {
- err = -ENOMEM;
- goto out_err;
- }
- *pseg = seg;
- seg->next = NULL;
if (copy_from_user(seg + 1, src, alen)) {
err = -EFAULT;
goto out_err;
}
- pseg = &seg->next;
+ seg = seg->next;
len -= alen;
src = ((char __user *)src) + alen;
}
_
Patches currently in -mm which might be from peter@xxxxxxxxxxxxxxxxxx are
origin.patch
ipc-fix-potential-oops-when-src-msg-4k-w-msg_copy.patch
ipc-dont-allocate-a-copy-larger-than-max.patch
ipc-clamp-with-min.patch
ipc-separate-msg-allocation-from-userspace-copy.patch
ipc-tighten-msg-copy-loops.patch
ipc-set-efault-as-default-error-in-load_msg.patch
ipc-remove-msg-handling-from-queue-scan.patch
ipc-implement-msg_copy-as-a-new-receive-mode.patch
ipc-simplify-msg-list-search.patch
ipc-refactor-msg-list-search-into-separate-function.patch
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