[PATCH AUTOSEL 4.14 31/46] IB/usnic: Update with bug fixes from core code

From: Sasha Levin
Date: Thu Oct 25 2018 - 10:11:43 EST

From: Jason Gunthorpe <jgg@xxxxxxxxxxxx>

[ Upstream commit 43cbd64b1fdc1da89abdad88a022d9e87a98e9c6 ]

usnic has a modified version of the core codes' ib_umem_get() and
related, and the copy misses many of the bug fixes done over the years:

Commit bc3e53f682d9 ("mm: distinguish between mlocked and pinned pages")
Commit 87773dd56d54 ("IB: ib_umem_release() should decrement mm->pinned_vm
from ib_umem_get")
Commit 8494057ab5e4 ("IB/uverbs: Prevent integer overflow in ib_umem_get
address arithmetic")
Commit 8abaae62f3fd ("IB/core: disallow registering 0-sized memory region")
Commit 66578b0b2f69 ("IB/core: don't disallow registering region starting
at 0x0")
Commit 53376fedb9da ("RDMA/core: not to set page dirty bit if it's already
set.")
Commit 8e907ed48827 ("IB/umem: Use the correct mm during ib_umem_release")

Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/hw/usnic/usnic_ib_verbs.c | 2 +-
drivers/infiniband/hw/usnic/usnic_uiom.c | 40 ++++++++++++++------
drivers/infiniband/hw/usnic/usnic_uiom.h | 5 ++-
3 files changed, 33 insertions(+), 14 deletions(-)

diff --git a/drivers/infiniband/hw/usnic/usnic_ib_verbs.c b/drivers/infiniband/hw/usnic/usnic_ib_verbs.c
index e4113ef09315..3c3453d213dc 100644
--- a/drivers/infiniband/hw/usnic/usnic_ib_verbs.c
+++ b/drivers/infiniband/hw/usnic/usnic_ib_verbs.c
@@ -642,7 +642,7 @@ int usnic_ib_dereg_mr(struct ib_mr *ibmr)

usnic_dbg("va 0x%lx length 0x%zx\n", mr->umem->va, mr->umem->length);

- usnic_uiom_reg_release(mr->umem, ibmr->pd->uobject->context->closing);
+ usnic_uiom_reg_release(mr->umem, ibmr->uobject->context);
kfree(mr);
return 0;
}
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c
index 4381c0a9a873..9dd39daa602b 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom.c
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.c
@@ -41,6 +41,7 @@
#include <linux/workqueue.h>
#include <linux/list.h>
#include <linux/pci.h>
+#include <rdma/ib_verbs.h>

#include "usnic_log.h"
#include "usnic_uiom.h"
@@ -88,7 +89,7 @@ static void usnic_uiom_put_pages(struct list_head *chunk_list, int dirty)
for_each_sg(chunk->page_list, sg, chunk->nents, i) {
page = sg_page(sg);
pa = sg_phys(sg);
- if (dirty)
+ if (!PageDirty(page) && dirty)
set_page_dirty_lock(page);
put_page(page);
usnic_dbg("pa: %pa\n", &pa);
@@ -114,6 +115,16 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
dma_addr_t pa;
unsigned int gup_flags;

+ /*
+ * If the combination of the addr and size requested for this memory
+ * region causes an integer overflow, return error.
+ */
+ if (((addr + size) < addr) || PAGE_ALIGN(addr + size) < (addr + size))
+ return -EINVAL;
+
+ if (!size)
+ return -EINVAL;
+
if (!can_do_mlock())
return -EPERM;

@@ -127,7 +138,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,

down_write(&current->mm->mmap_sem);

- locked = npages + current->mm->locked_vm;
+ locked = npages + current->mm->pinned_vm;
lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;

if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
@@ -143,7 +154,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
ret = 0;

while (npages) {
- ret = get_user_pages(cur_base,
+ ret = get_user_pages_longterm(cur_base,
min_t(unsigned long, npages,
PAGE_SIZE / sizeof(struct page *)),
gup_flags, page_list, NULL);
@@ -186,7 +197,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
if (ret < 0)
usnic_uiom_put_pages(chunk_list, 0);
else
- current->mm->locked_vm = locked;
+ current->mm->pinned_vm = locked;

up_write(&current->mm->mmap_sem);
free_page((unsigned long) page_list);
@@ -420,18 +431,22 @@ struct usnic_uiom_reg *usnic_uiom_reg_get(struct usnic_uiom_pd *pd,
return ERR_PTR(err);
}

-void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr, int closing)
+void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
+ struct ib_ucontext *ucontext)
{
+ struct task_struct *task;
struct mm_struct *mm;
unsigned long diff;

__usnic_uiom_reg_release(uiomr->pd, uiomr, 1);

- mm = get_task_mm(current);
- if (!mm) {
- kfree(uiomr);
- return;
- }
+ task = get_pid_task(ucontext->tgid, PIDTYPE_PID);
+ if (!task)
+ goto out;
+ mm = get_task_mm(task);
+ put_task_struct(task);
+ if (!mm)
+ goto out;

diff = PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;

@@ -443,7 +458,7 @@ void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr, int closing)
* up here and not be able to take the mmap_sem. In that case
* we defer the vm_locked accounting to the system workqueue.
*/
- if (closing) {
+ if (ucontext->closing) {
if (!down_write_trylock(&mm->mmap_sem)) {
INIT_WORK(&uiomr->work, usnic_uiom_reg_account);
uiomr->mm = mm;
@@ -455,9 +470,10 @@ void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr, int closing)
} else
down_write(&mm->mmap_sem);

- current->mm->locked_vm -= diff;
+ mm->pinned_vm -= diff;
up_write(&mm->mmap_sem);
mmput(mm);
+out:
kfree(uiomr);
}

diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.h b/drivers/infiniband/hw/usnic/usnic_uiom.h
index 431efe4143f4..8c096acff123 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom.h
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.h
@@ -39,6 +39,8 @@

#include "usnic_uiom_interval_tree.h"

+struct ib_ucontext;
+
#define USNIC_UIOM_READ (1)
#define USNIC_UIOM_WRITE (2)

@@ -89,7 +91,8 @@ void usnic_uiom_free_dev_list(struct device **devs);
struct usnic_uiom_reg *usnic_uiom_reg_get(struct usnic_uiom_pd *pd,
unsigned long addr, size_t size,
int access, int dmasync);
-void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr, int closing);
+void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
+ struct ib_ucontext *ucontext);
int usnic_uiom_init(char *drv_name);
void usnic_uiom_fini(void);
#endif /* USNIC_UIOM_H_ */
--
2.17.1