There was no more caller passing vm_flags to do_mmap(), and vm_flags was
removed from the function's input by:
commit 45e55300f114 ("mm: remove unnecessary wrapper function do_mmap_pgoff()").
There is a new user now. Shadow stack allocation passes VM_SHSTK to
do_mmap(). Re-introduce vm_flags to do_mmap(), but without the old wrapper
do_mmap_pgoff(). Instead, make all callers of the wrapper pass a zero
vm_flags to do_mmap().
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
Reviewed-by: Peter Collingbourne <pcc@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
---
fs/aio.c | 2 +-
include/linux/mm.h | 3 ++-
ipc/shm.c | 2 +-
mm/mmap.c | 10 +++++-----
mm/nommu.c | 4 ++--
mm/util.c | 2 +-
6 files changed, 12 insertions(+), 11 deletions(-)
diff --git a/fs/aio.c b/fs/aio.c
index 1f32da13d39e..b5d0586209a7 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -529,7 +529,7 @@ static int aio_setup_ring(struct kioctx *ctx, unsigned int nr_events)
ctx->mmap_base = do_mmap(ctx->aio_ring_file, 0, ctx->mmap_size,
PROT_READ | PROT_WRITE,
- MAP_SHARED, 0, &unused, NULL);
+ MAP_SHARED, 0, 0, &unused, NULL);
mmap_write_unlock(mm);
if (IS_ERR((void *)ctx->mmap_base)) {
ctx->mmap_size = 0;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index e363173f7634..2731889f49c1 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2543,7 +2543,8 @@ extern unsigned long mmap_region(struct file *file, unsigned long addr,
struct list_head *uf);
extern unsigned long do_mmap(struct file *file, unsigned long addr,
unsigned long len, unsigned long prot, unsigned long flags,
- unsigned long pgoff, unsigned long *populate, struct list_head *uf);
+ vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
+ struct list_head *uf);
extern int __do_munmap(struct mm_struct *, unsigned long, size_t,
struct list_head *uf, bool downgrade);
extern int do_munmap(struct mm_struct *, unsigned long, size_t,
diff --git a/ipc/shm.c b/ipc/shm.c
index febd88daba8c..b6370eb1eaab 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1556,7 +1556,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
goto invalid;
}
- addr = do_mmap(file, addr, size, prot, flags, 0, &populate, NULL);
+ addr = do_mmap(file, addr, size, prot, flags, 0, 0, &populate, NULL);
*raddr = addr;
err = 0;
if (IS_ERR_VALUE(addr))
diff --git a/mm/mmap.c b/mm/mmap.c
index 2ac67882ace2..99077171010b 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1401,11 +1401,11 @@ static inline bool file_mmap_ok(struct file *file, struct inode *inode,
*/
unsigned long do_mmap(struct file *file, unsigned long addr,
unsigned long len, unsigned long prot,
- unsigned long flags, unsigned long pgoff,
- unsigned long *populate, struct list_head *uf)
+ unsigned long flags, vm_flags_t vm_flags,
+ unsigned long pgoff, unsigned long *populate,
+ struct list_head *uf)
{
struct mm_struct *mm = current->mm;
- vm_flags_t vm_flags;
int pkey = 0;
*populate = 0;
@@ -1467,7 +1467,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
* to. we assume access permissions have been handled by the open
* of the memory object, so we don't do any here.
*/
- vm_flags = calc_vm_prot_bits(prot, pkey) | calc_vm_flag_bits(flags) |
+ vm_flags |= calc_vm_prot_bits(prot, pkey) | calc_vm_flag_bits(flags) |
mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
if (flags & MAP_LOCKED)
@@ -3047,7 +3047,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
file = get_file(vma->vm_file);
ret = do_mmap(vma->vm_file, start, size,
- prot, flags, pgoff, &populate, NULL);
+ prot, flags, 0, pgoff, &populate, NULL);
fput(file);
out:
mmap_write_unlock(mm);
diff --git a/mm/nommu.c b/mm/nommu.c
index 5c9ab799c0e6..9b6f7a1895c2 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1071,6 +1071,7 @@ unsigned long do_mmap(struct file *file,
unsigned long len,
unsigned long prot,
unsigned long flags,
+ vm_flags_t vm_flags,
unsigned long pgoff,
unsigned long *populate,
struct list_head *uf)
@@ -1078,7 +1079,6 @@ unsigned long do_mmap(struct file *file,
struct vm_area_struct *vma;
struct vm_region *region;
struct rb_node *rb;
- vm_flags_t vm_flags;
unsigned long capabilities, result;
int ret;
@@ -1097,7 +1097,7 @@ unsigned long do_mmap(struct file *file,
/* we've determined that we can make the mapping, now translate what we
* now know into VMA flags */
- vm_flags = determine_vm_flags(file, prot, flags, capabilities);
+ vm_flags |= determine_vm_flags(file, prot, flags, capabilities);
/* we're going to need to record the mapping */
region = kmem_cache_zalloc(vm_region_jar, GFP_KERNEL);
diff --git a/mm/util.c b/mm/util.c
index 54870226cea6..49cbd4400d13 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -516,7 +516,7 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
if (!ret) {
if (mmap_write_lock_killable(mm))
return -EINTR;
- ret = do_mmap(file, addr, len, prot, flag, pgoff, &populate,
+ ret = do_mmap(file, addr, len, prot, flag, 0, pgoff, &populate,
&uf);
mmap_write_unlock(mm);
userfaultfd_unmap_complete(mm, &uf);
--
2.21.0
