The change moving addr_lsb into the _sigfault union failed to take into account that _sigfault._addr_bnd._lower being a pointer forced the entire union to have pointer alignment. In practice this only mattered for the offset of si_pkey which is why this has taken so long to discover. To correct this change _dummy_pkey and _dummy_bnd to have pointer type.
Unified · Split
| @@ -229,13 +229,13 @@ typedef struct compat_siginfo { · 228 unmodified lines | ||
| 229 | 229 | short int _addr_lsb; /* Valid LSB of the reported address. */ |
| 230 | 230 | /* used when si_code=SEGV_BNDERR */ |
| 231 | 231 | struct { |
| 232 | − short _dummy_bnd; | |
| 232 | + compat_uptr_t _dummy_bnd; | |
| 233 | 233 | compat_uptr_t _lower; |
| 234 | 234 | compat_uptr_t _upper; |
| 235 | 235 | } _addr_bnd; |
| 236 | 236 | /* used when si_code=SEGV_PKUERR */ |
| 237 | 237 | struct { |
| 238 | − short _dummy_pkey; | |
| 238 | + compat_uptr_t _dummy_pkey; | |
| 239 | 239 | u32 _pkey; |
| 240 | 240 | } _addr_pkey; |
| 241 | 241 | }; |
| @@ -102,13 +102,13 @@ typedef struct siginfo { · 101 unmodified lines | ||
| 102 | 102 | short _addr_lsb; /* LSB of the reported address */ |
| 103 | 103 | /* used when si_code=SEGV_BNDERR */ |
| 104 | 104 | struct { |
| 105 | − short _dummy_bnd; | |
| 105 | + void *_dummy_bnd; | |
| 106 | 106 | void __user *_lower; |
| 107 | 107 | void __user *_upper; |
| 108 | 108 | } _addr_bnd; |
| 109 | 109 | /* used when si_code=SEGV_PKUERR */ |
| 110 | 110 | struct { |
| 111 | − short _dummy_pkey; | |
| 111 | + void *_dummy_pkey; | |
| 112 | 112 | __u32 _pkey; |
| 113 | 113 | } _addr_pkey; |
| 114 | 114 | }; |