move aio compat to fs/aio.c

... and fix the minor buglet in compat io_submit() - native one
kills ioctx as cleanup when put_user() fails.  Get rid of
bogus compat_... in !CONFIG_AIO case, while we are at it - they
should simply fail with ENOSYS, same as for native counterparts.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2016-12-20 07:04:57 -05:00
parent e93b1cc8a8
commit c00d2c7e89
4 changed files with 98 additions and 82 deletions

View File

@@ -1367,6 +1367,39 @@ out:
return ret;
}
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE2(io_setup, unsigned, nr_events, u32 __user *, ctx32p)
{
struct kioctx *ioctx = NULL;
unsigned long ctx;
long ret;
ret = get_user(ctx, ctx32p);
if (unlikely(ret))
goto out;
ret = -EINVAL;
if (unlikely(ctx || nr_events == 0)) {
pr_debug("EINVAL: ctx %lu nr_events %u\n",
ctx, nr_events);
goto out;
}
ioctx = ioctx_alloc(nr_events);
ret = PTR_ERR(ioctx);
if (!IS_ERR(ioctx)) {
/* truncating is ok because it's a user address */
ret = put_user((u32)ioctx->user_id, ctx32p);
if (ret)
kill_ioctx(current->mm, ioctx, NULL);
percpu_ref_put(&ioctx->users);
}
out:
return ret;
}
#endif
/* sys_io_destroy:
* Destroy the aio_context specified. May cancel any outstanding
* AIOs and block on completion. Will fail with -ENOSYS if not
@@ -1591,8 +1624,8 @@ out_put_req:
return ret;
}
long do_io_submit(aio_context_t ctx_id, long nr,
struct iocb __user *__user *iocbpp, bool compat)
static long do_io_submit(aio_context_t ctx_id, long nr,
struct iocb __user *__user *iocbpp, bool compat)
{
struct kioctx *ctx;
long ret = 0;
@@ -1662,6 +1695,44 @@ SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr,
return do_io_submit(ctx_id, nr, iocbpp, 0);
}
#ifdef CONFIG_COMPAT
static inline long
copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64)
{
compat_uptr_t uptr;
int i;
for (i = 0; i < nr; ++i) {
if (get_user(uptr, ptr32 + i))
return -EFAULT;
if (put_user(compat_ptr(uptr), ptr64 + i))
return -EFAULT;
}
return 0;
}
#define MAX_AIO_SUBMITS (PAGE_SIZE/sizeof(struct iocb *))
COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id,
int, nr, u32 __user *, iocb)
{
struct iocb __user * __user *iocb64;
long ret;
if (unlikely(nr < 0))
return -EINVAL;
if (nr > MAX_AIO_SUBMITS)
nr = MAX_AIO_SUBMITS;
iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64));
ret = copy_iocb(nr, iocb, iocb64);
if (!ret)
ret = do_io_submit(ctx_id, nr, iocb64, 1);
return ret;
}
#endif
/* lookup_kiocb
* Finds a given iocb for cancellation.
*/
@@ -1761,3 +1832,25 @@ SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id,
}
return ret;
}
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE5(io_getevents, compat_aio_context_t, ctx_id,
compat_long_t, min_nr,
compat_long_t, nr,
struct io_event __user *, events,
struct compat_timespec __user *, timeout)
{
struct timespec t;
struct timespec __user *ut = NULL;
if (timeout) {
if (compat_get_timespec(&t, timeout))
return -EFAULT;
ut = compat_alloc_user_space(sizeof(*ut));
if (copy_to_user(ut, &t, sizeof(t)))
return -EFAULT;
}
return sys_io_getevents(ctx_id, min_nr, nr, events, ut);
}
#endif