| Message ID | 20250104063925.1544944-1-lsahn@ooseel.net (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: ensure the uniformity of arguments passed to do_mmap(..) | expand |
On Sat, Jan 04, 2025 at 03:39:25PM +0900, Leesoo Ahn wrote: > Standardize the way of passing a value to @populate parameter of do_mmap(..) > as follow: > > 1. Caller must initialize the variable to 0, except it's clarified as > the name of the variable, 'unused'. > 2. do_mmap(..) doesn't take care of its initialization. Why? This seems fragile.
diff --git a/mm/mmap.c b/mm/mmap.c index d32b7e701058..4aebb1440c35 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -289,8 +289,6 @@ unsigned long do_mmap(struct file *file, unsigned long addr, struct mm_struct *mm = current->mm; int pkey = 0; - *populate = 0; - if (!len) return -EINVAL; diff --git a/mm/nommu.c b/mm/nommu.c index 9cb6e99215e2..fa69cd8271af 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1016,8 +1016,6 @@ unsigned long do_mmap(struct file *file, int ret; VMA_ITERATOR(vmi, current->mm, 0); - *populate = 0; - /* decide whether we should attempt the mapping, and if so what sort of * mapping */ ret = validate_mmap_request(file, addr, len, prot, flags, pgoff, diff --git a/mm/util.c b/mm/util.c index c1c3b06ab4f9..728effcab217 100644 --- a/mm/util.c +++ b/mm/util.c @@ -570,7 +570,7 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr, { unsigned long ret; struct mm_struct *mm = current->mm; - unsigned long populate; + unsigned long populate = 0; LIST_HEAD(uf); ret = security_mmap_file(file, prot, flag);
Standardize the way of passing a value to @populate parameter of do_mmap(..) as follow: 1. Caller must initialize the variable to 0, except it's clarified as the name of the variable, 'unused'. 2. do_mmap(..) doesn't take care of its initialization. This patch has a couple of changes that: - callers initialize the variable to 0. - remove the line of initialization inside do_mmap(..) Signed-off-by: Leesoo Ahn <lsahn@ooseel.net> --- mm/mmap.c | 2 -- mm/nommu.c | 2 -- mm/util.c | 2 +- 3 files changed, 1 insertion(+), 5 deletions(-)