[PATCH v6 8/8] media: v4l2-core: fix compat v4l2_buffer handling for time64 ABI
From: Arnd Bergmann
Date: Mon Dec 16 2019 - 09:15:31 EST
Add support for the four new variants of ioctl commands for 64-bit time_t
in v4l2_buffer.
The existing v4l2_buffer32 structure for the traditional format gets
changed to match the new v4l2_buffer format, and the old layout is
now called v4l2_buffer32_time32. Neither of these matches the native
64-bit architecture format of v4l2_buffer, so both require special
handling in compat code.
Duplicating the existing handlers for the new types is a safe conversion
for now, but unfortunately this may turn into a maintenance burden
later. A larger-scale rework of the compat code might be a better
alternative, but is out of scope of the y2038 work.
Note: x32 support for v4l2_buffer32 has always been broken and remains
so after this change, fixing it would have required even more duplication,
and apparently nobody has cared so far.
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 269 +++++++++++++++++-
1 file changed, 268 insertions(+), 1 deletion(-)
diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
index f8a4b0ddd47d..381d29e45a49 100644
--- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
+++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
@@ -468,13 +468,43 @@ struct v4l2_plane32 {
__u32 reserved[11];
};
+/*
+ * This is correct for all architectures including i386, but not x32,
+ * which has different alignment requirements for timestamp
+ */
struct v4l2_buffer32 {
__u32 index;
__u32 type; /* enum v4l2_buf_type */
__u32 bytesused;
__u32 flags;
__u32 field; /* enum v4l2_field */
- struct compat_timeval timestamp;
+ struct {
+ compat_s64 tv_sec;
+ compat_s64 tv_usec;
+ } timestamp;
+ struct v4l2_timecode timecode;
+ __u32 sequence;
+
+ /* memory location */
+ __u32 memory; /* enum v4l2_memory */
+ union {
+ __u32 offset;
+ compat_long_t userptr;
+ compat_caddr_t planes;
+ __s32 fd;
+ } m;
+ __u32 length;
+ __u32 reserved2;
+ __s32 request_fd;
+};
+
+struct v4l2_buffer32_time32 {
+ __u32 index;
+ __u32 type; /* enum v4l2_buf_type */
+ __u32 bytesused;
+ __u32 flags;
+ __u32 field; /* enum v4l2_field */
+ struct old_timeval32 timestamp;
struct v4l2_timecode timecode;
__u32 sequence;
@@ -581,6 +611,31 @@ static int bufsize_v4l2_buffer(struct v4l2_buffer32 __user *p32, u32 *size)
return 0;
}
+static int bufsize_v4l2_buffer_time32(struct v4l2_buffer32_time32 __user *p32, u32 *size)
+{
+ u32 type;
+ u32 length;
+
+ if (!access_ok(p32, sizeof(*p32)) ||
+ get_user(type, &p32->type) ||
+ get_user(length, &p32->length))
+ return -EFAULT;
+
+ if (V4L2_TYPE_IS_MULTIPLANAR(type)) {
+ if (length > VIDEO_MAX_PLANES)
+ return -EINVAL;
+
+ /*
+ * We don't really care if userspace decides to kill itself
+ * by passing a very big length value
+ */
+ *size = length * sizeof(struct v4l2_plane);
+ } else {
+ *size = 0;
+ }
+ return 0;
+}
+
static int get_v4l2_buffer32(struct v4l2_buffer __user *p64,
struct v4l2_buffer32 __user *p32,
void __user *aux_buf, u32 aux_space)
@@ -681,6 +736,106 @@ static int get_v4l2_buffer32(struct v4l2_buffer __user *p64,
return 0;
}
+static int get_v4l2_buffer32_time32(struct v4l2_buffer_time32 __user *p64,
+ struct v4l2_buffer32_time32 __user *p32,
+ void __user *aux_buf, u32 aux_space)
+{
+ u32 type;
+ u32 length;
+ s32 request_fd;
+ enum v4l2_memory memory;
+ struct v4l2_plane32 __user *uplane32;
+ struct v4l2_plane __user *uplane;
+ compat_caddr_t p;
+ int ret;
+
+ if (!access_ok(p32, sizeof(*p32)) ||
+ assign_in_user(&p64->index, &p32->index) ||
+ get_user(type, &p32->type) ||
+ put_user(type, &p64->type) ||
+ assign_in_user(&p64->flags, &p32->flags) ||
+ get_user(memory, &p32->memory) ||
+ put_user(memory, &p64->memory) ||
+ get_user(length, &p32->length) ||
+ put_user(length, &p64->length) ||
+ get_user(request_fd, &p32->request_fd) ||
+ put_user(request_fd, &p64->request_fd))
+ return -EFAULT;
+
+ if (V4L2_TYPE_IS_OUTPUT(type))
+ if (assign_in_user(&p64->bytesused, &p32->bytesused) ||
+ assign_in_user(&p64->field, &p32->field) ||
+ assign_in_user(&p64->timestamp.tv_sec,
+ &p32->timestamp.tv_sec) ||
+ assign_in_user(&p64->timestamp.tv_usec,
+ &p32->timestamp.tv_usec))
+ return -EFAULT;
+
+ if (V4L2_TYPE_IS_MULTIPLANAR(type)) {
+ u32 num_planes = length;
+
+ if (num_planes == 0) {
+ /*
+ * num_planes == 0 is legal, e.g. when userspace doesn't
+ * need planes array on DQBUF
+ */
+ return put_user(NULL, &p64->m.planes);
+ }
+ if (num_planes > VIDEO_MAX_PLANES)
+ return -EINVAL;
+
+ if (get_user(p, &p32->m.planes))
+ return -EFAULT;
+
+ uplane32 = compat_ptr(p);
+ if (!access_ok(uplane32,
+ num_planes * sizeof(*uplane32)))
+ return -EFAULT;
+
+ /*
+ * We don't really care if userspace decides to kill itself
+ * by passing a very big num_planes value
+ */
+ if (aux_space < num_planes * sizeof(*uplane))
+ return -EFAULT;
+
+ uplane = aux_buf;
+ if (put_user_force(uplane, &p64->m.planes))
+ return -EFAULT;
+
+ while (num_planes--) {
+ ret = get_v4l2_plane32(uplane, uplane32, memory);
+ if (ret)
+ return ret;
+ uplane++;
+ uplane32++;
+ }
+ } else {
+ switch (memory) {
+ case V4L2_MEMORY_MMAP:
+ case V4L2_MEMORY_OVERLAY:
+ if (assign_in_user(&p64->m.offset, &p32->m.offset))
+ return -EFAULT;
+ break;
+ case V4L2_MEMORY_USERPTR: {
+ compat_ulong_t userptr;
+
+ if (get_user(userptr, &p32->m.userptr) ||
+ put_user((unsigned long)compat_ptr(userptr),
+ &p64->m.userptr))
+ return -EFAULT;
+ break;
+ }
+ case V4L2_MEMORY_DMABUF:
+ if (assign_in_user(&p64->m.fd, &p32->m.fd))
+ return -EFAULT;
+ break;
+ }
+ }
+
+ return 0;
+}
+
static int put_v4l2_buffer32(struct v4l2_buffer __user *p64,
struct v4l2_buffer32 __user *p32)
{
@@ -761,6 +916,87 @@ static int put_v4l2_buffer32(struct v4l2_buffer __user *p64,
return 0;
}
+
+static int put_v4l2_buffer32_time32(struct v4l2_buffer_time32 __user *p64,
+ struct v4l2_buffer32_time32 __user *p32)
+{
+ u32 type;
+ u32 length;
+ enum v4l2_memory memory;
+ struct v4l2_plane32 __user *uplane32;
+ struct v4l2_plane *uplane;
+ compat_caddr_t p;
+ int ret;
+
+ if (!access_ok(p32, sizeof(*p32)) ||
+ assign_in_user(&p32->index, &p64->index) ||
+ get_user(type, &p64->type) ||
+ put_user(type, &p32->type) ||
+ assign_in_user(&p32->flags, &p64->flags) ||
+ get_user(memory, &p64->memory) ||
+ put_user(memory, &p32->memory))
+ return -EFAULT;
+
+ if (assign_in_user(&p32->bytesused, &p64->bytesused) ||
+ assign_in_user(&p32->field, &p64->field) ||
+ assign_in_user(&p32->timestamp.tv_sec, &p64->timestamp.tv_sec) ||
+ assign_in_user(&p32->timestamp.tv_usec, &p64->timestamp.tv_usec) ||
+ copy_in_user(&p32->timecode, &p64->timecode, sizeof(p64->timecode)) ||
+ assign_in_user(&p32->sequence, &p64->sequence) ||
+ assign_in_user(&p32->reserved2, &p64->reserved2) ||
+ assign_in_user(&p32->request_fd, &p64->request_fd) ||
+ get_user(length, &p64->length) ||
+ put_user(length, &p32->length))
+ return -EFAULT;
+
+ if (V4L2_TYPE_IS_MULTIPLANAR(type)) {
+ u32 num_planes = length;
+
+ if (num_planes == 0)
+ return 0;
+ /* We need to define uplane without __user, even though
+ * it does point to data in userspace here. The reason is
+ * that v4l2-ioctl.c copies it from userspace to kernelspace,
+ * so its definition in videodev2.h doesn't have a
+ * __user markup. Defining uplane with __user causes
+ * smatch warnings, so instead declare it without __user
+ * and cast it as a userspace pointer to put_v4l2_plane32().
+ */
+ if (get_user(uplane, &p64->m.planes))
+ return -EFAULT;
+ if (get_user(p, &p32->m.planes))
+ return -EFAULT;
+ uplane32 = compat_ptr(p);
+
+ while (num_planes--) {
+ ret = put_v4l2_plane32((void __user *)uplane,
+ uplane32, memory);
+ if (ret)
+ return ret;
+ ++uplane;
+ ++uplane32;
+ }
+ } else {
+ switch (memory) {
+ case V4L2_MEMORY_MMAP:
+ case V4L2_MEMORY_OVERLAY:
+ if (assign_in_user(&p32->m.offset, &p64->m.offset))
+ return -EFAULT;
+ break;
+ case V4L2_MEMORY_USERPTR:
+ if (assign_in_user(&p32->m.userptr, &p64->m.userptr))
+ return -EFAULT;
+ break;
+ case V4L2_MEMORY_DMABUF:
+ if (assign_in_user(&p32->m.fd, &p64->m.fd))
+ return -EFAULT;
+ break;
+ }
+ }
+
+ return 0;
+}
+
struct v4l2_framebuffer32 {
__u32 capability;
__u32 flags;
@@ -1150,10 +1386,13 @@ static int put_v4l2_edid32(struct v4l2_edid __user *p64,
#define VIDIOC_G_FMT32 _IOWR('V', 4, struct v4l2_format32)
#define VIDIOC_S_FMT32 _IOWR('V', 5, struct v4l2_format32)
#define VIDIOC_QUERYBUF32 _IOWR('V', 9, struct v4l2_buffer32)
+#define VIDIOC_QUERYBUF32_TIME32 _IOWR('V', 9, struct v4l2_buffer32_time32)
#define VIDIOC_G_FBUF32 _IOR ('V', 10, struct v4l2_framebuffer32)
#define VIDIOC_S_FBUF32 _IOW ('V', 11, struct v4l2_framebuffer32)
#define VIDIOC_QBUF32 _IOWR('V', 15, struct v4l2_buffer32)
+#define VIDIOC_QBUF32_TIME32 _IOWR('V', 15, struct v4l2_buffer32_time32)
#define VIDIOC_DQBUF32 _IOWR('V', 17, struct v4l2_buffer32)
+#define VIDIOC_DQBUF32_TIME32 _IOWR('V', 17, struct v4l2_buffer32_time32)
#define VIDIOC_ENUMSTD32 _IOWR('V', 25, struct v4l2_standard32)
#define VIDIOC_ENUMINPUT32 _IOWR('V', 26, struct v4l2_input32)
#define VIDIOC_G_EDID32 _IOWR('V', 40, struct v4l2_edid32)
@@ -1166,6 +1405,7 @@ static int put_v4l2_edid32(struct v4l2_edid __user *p64,
#define VIDIOC_DQEVENT32_TIME32 _IOR ('V', 89, struct v4l2_event32_time32)
#define VIDIOC_CREATE_BUFS32 _IOWR('V', 92, struct v4l2_create_buffers32)
#define VIDIOC_PREPARE_BUF32 _IOWR('V', 93, struct v4l2_buffer32)
+#define VIDIOC_PREPARE_BUF32_TIME32 _IOWR('V', 93, struct v4l2_buffer32_time32)
#define VIDIOC_OVERLAY32 _IOW ('V', 14, s32)
#define VIDIOC_STREAMON32 _IOW ('V', 18, s32)
@@ -1235,10 +1475,13 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
case VIDIOC_G_FMT32: ncmd = VIDIOC_G_FMT; break;
case VIDIOC_S_FMT32: ncmd = VIDIOC_S_FMT; break;
case VIDIOC_QUERYBUF32: ncmd = VIDIOC_QUERYBUF; break;
+ case VIDIOC_QUERYBUF32_TIME32: ncmd = VIDIOC_QUERYBUF_TIME32; break;
case VIDIOC_G_FBUF32: ncmd = VIDIOC_G_FBUF; break;
case VIDIOC_S_FBUF32: ncmd = VIDIOC_S_FBUF; break;
case VIDIOC_QBUF32: ncmd = VIDIOC_QBUF; break;
+ case VIDIOC_QBUF32_TIME32: ncmd = VIDIOC_QBUF_TIME32; break;
case VIDIOC_DQBUF32: ncmd = VIDIOC_DQBUF; break;
+ case VIDIOC_DQBUF32_TIME32: ncmd = VIDIOC_DQBUF_TIME32; break;
case VIDIOC_ENUMSTD32: ncmd = VIDIOC_ENUMSTD; break;
case VIDIOC_ENUMINPUT32: ncmd = VIDIOC_ENUMINPUT; break;
case VIDIOC_TRY_FMT32: ncmd = VIDIOC_TRY_FMT; break;
@@ -1258,6 +1501,7 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
case VIDIOC_S_OUTPUT32: ncmd = VIDIOC_S_OUTPUT; break;
case VIDIOC_CREATE_BUFS32: ncmd = VIDIOC_CREATE_BUFS; break;
case VIDIOC_PREPARE_BUF32: ncmd = VIDIOC_PREPARE_BUF; break;
+ case VIDIOC_PREPARE_BUF32_TIME32: ncmd = VIDIOC_PREPARE_BUF_TIME32; break;
case VIDIOC_G_EDID32: ncmd = VIDIOC_G_EDID; break;
case VIDIOC_S_EDID32: ncmd = VIDIOC_S_EDID; break;
default: ncmd = cmd; break;
@@ -1339,6 +1583,22 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
compatible_arg = 0;
break;
+ case VIDIOC_PREPARE_BUF32_TIME32:
+ case VIDIOC_QUERYBUF32_TIME32:
+ case VIDIOC_QBUF32_TIME32:
+ case VIDIOC_DQBUF32_TIME32:
+ err = bufsize_v4l2_buffer_time32(p32, &aux_space);
+ if (!err)
+ err = alloc_userspace(sizeof(struct v4l2_buffer),
+ aux_space, &new_p64);
+ if (!err) {
+ aux_buf = new_p64 + sizeof(struct v4l2_buffer);
+ err = get_v4l2_buffer32_time32(new_p64, p32,
+ aux_buf, aux_space);
+ }
+ compatible_arg = 0;
+ break;
+
case VIDIOC_S_FBUF32:
err = alloc_userspace(sizeof(struct v4l2_framebuffer), 0,
&new_p64);
@@ -1487,6 +1747,13 @@ static long do_video_ioctl(struct file *file, unsigned int cmd, unsigned long ar
err = put_v4l2_buffer32(new_p64, p32);
break;
+ case VIDIOC_PREPARE_BUF32_TIME32:
+ case VIDIOC_QUERYBUF32_TIME32:
+ case VIDIOC_QBUF32_TIME32:
+ case VIDIOC_DQBUF32_TIME32:
+ err = put_v4l2_buffer32_time32(new_p64, p32);
+ break;
+
case VIDIOC_ENUMSTD32:
err = put_v4l2_standard32(new_p64, p32);
break;
--
2.20.0