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Sashiko AI review found 1 potential issue(= s) to consider: - [Low] proc: define and initialize __free(kvfree) variable buf in one stat= ement in pde_read_buf() -- commit f2c1eb05c1e48ef170c932c3f77db0e09db3d058 Author: Christian Brauner proc: let procfs copy out reads that don't go through seq_file This commit adds a proc_read_buf callback to struct proc_ops so procfs entries can fill a kernel buffer while pinned and let procfs copy the buffer to userspace after unpinning the entry. > diff --git a/fs/proc/inode.c b/fs/proc/inode.c > index c0bb40e7ff964..3f29a1663d266 100644 > --- a/fs/proc/inode.c > +++ b/fs/proc/inode.c [ ... ] > @@ -400,11 +402,67 @@ static loff_t proc_reg_llseek(struct file *file, lo= ff_t offset, int whence) > return rv; > } > =20 > +/* > + * The entry fills a kernel buffer and procfs copies that to userspace a= fter > + * unpinning the entry. A reader that faults on its buffer then doesn't = hold > + * up remove_proc_entry(). > + */ > +static ssize_t pde_read_buf(struct proc_dir_entry *pde, struct kiocb *io= cb, > + struct iov_iter *iter) > +{ > + struct file *file =3D iocb->ki_filp; > + char *buf __free(kvfree) =3D NULL; > + ssize_t rv, done =3D 0; > + size_t len, count; > + loff_t pos; > + > + if (!iov_iter_count(iter)) > + return 0; > + /* neither the allocation nor the entry can honor IOCB_NOWAIT */ > + if ((iocb->ki_flags & IOCB_NOWAIT) && !(file->f_flags & O_NONBLOCK)) > + return -EAGAIN; > + len =3D min_t(size_t, iov_iter_count(iter), pde->read_size); > + buf =3D kvmalloc(len, GFP_KERNEL); [Severity: Low] This isn't a bug, but in pde_read_buf(), buf is declared with __free(kvfree) =3D NULL at the top of the function before the early return checks for !iov_iter_count(iter) and IOCB_NOWAIT, and then assigned separately via kvmalloc(). Could buf be defined and initialized in a single statement at the allocation site (char *buf __free(kvfree) =3D kvmalloc(len, GFP_KERNEL);) to follow the cleanup.h conventions? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261102-work-procf= s-core-v1-0-75df35e4f8b8@kernel.org?part=3D13