The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
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| @@ -28,7 +28,7 @@ struct tcpa_event { · 27 unmodified lines | ||
| 28 | 28 | u32 event_type; |
| 29 | 29 | u8 pcr_value[20]; /* SHA1 */ |
| 30 | 30 | u32 event_size; |
| 31 | − u8 event_data[0]; | |
| 31 | + u8 event_data[]; | |
| 32 | 32 | }; |
| 33 | 33 | |
| 34 | 34 | enum tcpa_event_types { |
| @@ -55,7 +55,7 @@ enum tcpa_event_types { · 20 unmodified lines | ||
| 55 | 55 | struct tcpa_pc_event { |
| 56 | 56 | u32 event_id; |
| 57 | 57 | u32 event_size; |
| 58 | − u8 event_data[0]; | |
| 58 | + u8 event_data[]; | |
| 59 | 59 | }; |
| 60 | 60 | |
| 61 | 61 | enum tcpa_pc_event_ids { |
| @@ -102,7 +102,7 @@ struct tcg_pcr_event { · 40 unmodified lines | ||
| 102 | 102 | |
| 103 | 103 | struct tcg_event_field { |
| 104 | 104 | u32 event_size; |
| 105 | − u8 event[0]; | |
| 105 | + u8 event[]; | |
| 106 | 106 | } __packed; |
| 107 | 107 | |
| 108 | 108 | struct tcg_pcr_event2_head { |