| Message ID | 014cd694-cc27-4a07-a34a-2ae95d744515@I-love.SAKURA.ne.jp (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/util: make memdup_user_nul() similar to memdup_user() | expand |
diff --git a/mm/util.c b/mm/util.c index c1c3b06ab4f9..60aa40f612b8 100644 --- a/mm/util.c +++ b/mm/util.c @@ -297,12 +297,7 @@ void *memdup_user_nul(const void __user *src, size_t len) { char *p; - /* - * Always use GFP_KERNEL, since copy_from_user() can sleep and - * cause pagefault, which makes it pointless to use GFP_NOFS - * or GFP_ATOMIC. - */ - p = kmalloc_track_caller(len + 1, GFP_KERNEL); + p = kmem_buckets_alloc_track_caller(user_buckets, len + 1, GFP_USER | __GFP_NOWARN); if (!p) return ERR_PTR(-ENOMEM);
Since the string data to copy from userspace is likely less than PAGE_SIZE bytes, replace GFP_KERNEL with GFP_USER like commit 6c2c97a24f09 ("memdup_user(): switch to GFP_USER") does and add __GFP_NOWARN like commit 6c8fcc096be9 ("mm: don't let userspace spam allocations warnings") does. Also, use dedicated slab buckets like commit d73778e4b867 ("mm/util: Use dedicated slab buckets for memdup_user()") does. Reported-by: syzbot+7e12e97b36154c54414b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7e12e97b36154c54414b Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> --- mm/util.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-)