2020-04-16 09:52:22

by Geert Uytterhoeven

[permalink] [raw]
Subject: [PATCH] virtchnl: Add missing explicit padding to structures

On e.g. m68k, the alignment of 32-bit values is only 2 bytes, leading
to:

./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:577:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:577:32: error: enumerator value for ‘virtchnl_static_assert_virtchnl_filter’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
^~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:619:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:619:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_pf_event’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);
^~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:640:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:640:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_iwarp_qv_info’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
^~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:647:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:647:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_iwarp_qvlist_info’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^

Fix this by adding explicit padding to structures with holes.

Reported-by: [email protected]
Signed-off-by: Geert Uytterhoeven <[email protected]>
---
Exposed by the "select PCI" in commit 4be5e8648b0c287a ("media: move CEC
platform drivers to a separate directory").
---
include/linux/avf/virtchnl.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/include/linux/avf/virtchnl.h b/include/linux/avf/virtchnl.h
index ca956b672ac0f759..40bad71865ea7628 100644
--- a/include/linux/avf/virtchnl.h
+++ b/include/linux/avf/virtchnl.h
@@ -476,6 +476,7 @@ struct virtchnl_rss_key {
u16 vsi_id;
u16 key_len;
u8 key[1]; /* RSS hash key, packed bytes */
+ u8 pad[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_key);
@@ -484,6 +485,7 @@ struct virtchnl_rss_lut {
u16 vsi_id;
u16 lut_entries;
u8 lut[1]; /* RSS lookup table */
+ u8 pad[1];
};

VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_lut);
@@ -572,6 +574,7 @@ struct virtchnl_filter {
enum virtchnl_action action;
u32 action_meta;
u8 field_flags;
+ u8 pad[3];
};

VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
@@ -610,6 +613,7 @@ struct virtchnl_pf_event {
/* link_speed provided in Mbps */
u32 link_speed;
u8 link_status;
+ u8 pad[3];
} link_event_adv;
} event_data;

@@ -635,6 +639,7 @@ struct virtchnl_iwarp_qv_info {
u16 ceq_idx;
u16 aeq_idx;
u8 itr_idx;
+ u8 pad[3];
};

VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
--
2.17.1


2020-04-22 18:52:41

by Bowers, AndrewX

[permalink] [raw]
Subject: RE: [Intel-wired-lan] [PATCH] virtchnl: Add missing explicit padding to structures

-----Original Message-----
From: Intel-wired-lan <[email protected]> On Behalf Of Geert Uytterhoeven
Sent: Thursday, April 16, 2020 2:51 AM
To: Kirsher, Jeffrey T <[email protected]>; David S . Miller <[email protected]>
Cc: [email protected]; [email protected]; [email protected]; Geert Uytterhoeven <[email protected]>
Subject: [Intel-wired-lan] [PATCH] virtchnl: Add missing explicit padding to structures

On e.g. m68k, the alignment of 32-bit values is only 2 bytes, leading
to:

./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:577:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:577:32: error: enumerator value for ‘virtchnl_static_assert_virtchnl_filter’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
^~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:619:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:619:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_pf_event’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);
^~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:640:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:640:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_iwarp_qv_info’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
^~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:647:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:647:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_iwarp_qvlist_info’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^

Fix this by adding explicit padding to structures with holes.

Reported-by: [email protected]
Signed-off-by: Geert Uytterhoeven <[email protected]>
---
Exposed by the "select PCI" in commit 4be5e8648b0c287a ("media: move CEC platform drivers to a separate directory").
---
include/linux/avf/virtchnl.h | 5 +++++
1 file changed, 5 insertions(+)

Tested-by: Andrew Bowers <[email protected]>