Due to an oversight when refactoring siginfo_t si_pkey has been in the wrong position since 4.16-rc1. Add an explicit check of the offset of every user space field in siginfo_t and compat_siginfo_t to make a mistake like this hard to make in the future. I have run this code on 4.15 and 4.16-rc1 with the position of si_pkey fixed and all of the fields show up in the same location.
Unified · Split
| @@ -43,6 +43,13 @@ static inline void signal_compat_build_tests(void) · 42 unmodified lines | |||
| 43 | BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields) != 3 * sizeof(int)); | 43 | BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields) != 3 * sizeof(int)); |
| 44 | #define CHECK_CSI_OFFSET(name) BUILD_BUG_ON(_sifields_offset != offsetof(compat_siginfo_t, _sifields.name)) | 44 | #define CHECK_CSI_OFFSET(name) BUILD_BUG_ON(_sifields_offset != offsetof(compat_siginfo_t, _sifields.name)) |
| 45 | 45 | ||
| 46 | BUILD_BUG_ON(offsetof(siginfo_t, si_signo) != 0); | ||
| 47 | BUILD_BUG_ON(offsetof(siginfo_t, si_errno) != 4); | ||
| 48 | BUILD_BUG_ON(offsetof(siginfo_t, si_code) != 8); | ||
| 49 | |||
| 50 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_signo) != 0); | ||
| 51 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_errno) != 4); | ||
| 52 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_code) != 8); | ||
| 46 | /* | 53 | /* |
| 47 | * Ensure that the size of each si_field never changes. | 54 | * Ensure that the size of each si_field never changes. |
| 48 | * If it does, it is a sign that the | 55 | * If it does, it is a sign that the |
| @@ -63,36 +70,94 @@ static inline void signal_compat_build_tests(void) · 14 unmodified lines | |||
| 63 | CHECK_CSI_SIZE (_kill, 2*sizeof(int)); | 70 | CHECK_CSI_SIZE (_kill, 2*sizeof(int)); |
| 64 | CHECK_SI_SIZE (_kill, 2*sizeof(int)); | 71 | CHECK_SI_SIZE (_kill, 2*sizeof(int)); |
| 65 | 72 | ||
| 73 | BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10); | ||
| 74 | BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14); | ||
| 75 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0xC); | ||
| 76 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10); | ||
| 77 | |||
| 66 | CHECK_CSI_OFFSET(_timer); | 78 | CHECK_CSI_OFFSET(_timer); |
| 67 | CHECK_CSI_SIZE (_timer, 3*sizeof(int)); | 79 | CHECK_CSI_SIZE (_timer, 3*sizeof(int)); |
| 68 | CHECK_SI_SIZE (_timer, 6*sizeof(int)); | 80 | CHECK_SI_SIZE (_timer, 6*sizeof(int)); |
| 69 | 81 | ||
| 82 | BUILD_BUG_ON(offsetof(siginfo_t, si_tid) != 0x10); | ||
| 83 | BUILD_BUG_ON(offsetof(siginfo_t, si_overrun) != 0x14); | ||
| 84 | BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18); | ||
| 85 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_tid) != 0x0C); | ||
| 86 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_overrun) != 0x10); | ||
| 87 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14); | ||
| 88 | |||
| 70 | CHECK_CSI_OFFSET(_rt); | 89 | CHECK_CSI_OFFSET(_rt); |
| 71 | CHECK_CSI_SIZE (_rt, 3*sizeof(int)); | 90 | CHECK_CSI_SIZE (_rt, 3*sizeof(int)); |
| 72 | CHECK_SI_SIZE (_rt, 4*sizeof(int)); | 91 | CHECK_SI_SIZE (_rt, 4*sizeof(int)); |
| 73 | 92 | ||
| 93 | BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10); | ||
| 94 | BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14); | ||
| 95 | BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x18); | ||
| 96 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0x0C); | ||
| 97 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10); | ||
| 98 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_value) != 0x14); | ||
| 99 | |||
| 74 | CHECK_CSI_OFFSET(_sigchld); | 100 | CHECK_CSI_OFFSET(_sigchld); |
| 75 | CHECK_CSI_SIZE (_sigchld, 5*sizeof(int)); | 101 | CHECK_CSI_SIZE (_sigchld, 5*sizeof(int)); |
| 76 | CHECK_SI_SIZE (_sigchld, 8*sizeof(int)); | 102 | CHECK_SI_SIZE (_sigchld, 8*sizeof(int)); |
| 77 | 103 | ||
| 104 | BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x10); | ||
| 105 | BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x14); | ||
| 106 | BUILD_BUG_ON(offsetof(siginfo_t, si_status) != 0x18); | ||
| 107 | BUILD_BUG_ON(offsetof(siginfo_t, si_utime) != 0x20); | ||
| 108 | BUILD_BUG_ON(offsetof(siginfo_t, si_stime) != 0x28); | ||
| 109 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pid) != 0x0C); | ||
| 110 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_uid) != 0x10); | ||
| 111 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_status) != 0x14); | ||
| 112 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_utime) != 0x18); | ||
| 113 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_stime) != 0x1C); | ||
| 114 | |||
| 78 | #ifdef CONFIG_X86_X32_ABI | 115 | #ifdef CONFIG_X86_X32_ABI |
| 79 | CHECK_CSI_OFFSET(_sigchld_x32); | 116 | CHECK_CSI_OFFSET(_sigchld_x32); |
| 80 | CHECK_CSI_SIZE (_sigchld_x32, 7*sizeof(int)); | 117 | CHECK_CSI_SIZE (_sigchld_x32, 7*sizeof(int)); |
| 81 | /* no _sigchld_x32 in the generic siginfo_t */ | 118 | /* no _sigchld_x32 in the generic siginfo_t */ |
| 119 | BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._utime) != 0x18); | ||
| 120 | BUILD_BUG_ON(offsetof(compat_siginfo_t, _sifields._sigchld_x32._stime) != 0x20); | ||
| 82 | #endif | 121 | #endif |
| 83 | 122 | ||
| 84 | CHECK_CSI_OFFSET(_sigfault); | 123 | CHECK_CSI_OFFSET(_sigfault); |
| 85 | CHECK_CSI_SIZE (_sigfault, 4*sizeof(int)); | 124 | CHECK_CSI_SIZE (_sigfault, 4*sizeof(int)); |
| 86 | CHECK_SI_SIZE (_sigfault, 8*sizeof(int)); | 125 | CHECK_SI_SIZE (_sigfault, 8*sizeof(int)); |
| 87 | 126 | ||
| 127 | BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x10); | ||
| 128 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr) != 0x0C); | ||
| 129 | |||
| 130 | BUILD_BUG_ON(offsetof(siginfo_t, si_addr_lsb) != 0x18); | ||
| 131 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_addr_lsb) != 0x10); | ||
| 132 | |||
| 133 | BUILD_BUG_ON(offsetof(siginfo_t, si_lower) != 0x20); | ||
| 134 | BUILD_BUG_ON(offsetof(siginfo_t, si_upper) != 0x28); | ||
| 135 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_lower) != 0x14); | ||
| 136 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_upper) != 0x18); | ||
| 137 | |||
| 138 | BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x20); | ||
| 139 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_pkey) != 0x14); | ||
| 140 | |||
| 88 | CHECK_CSI_OFFSET(_sigpoll); | 141 | CHECK_CSI_OFFSET(_sigpoll); |
| 89 | CHECK_CSI_SIZE (_sigpoll, 2*sizeof(int)); | 142 | CHECK_CSI_SIZE (_sigpoll, 2*sizeof(int)); |
| 90 | CHECK_SI_SIZE (_sigpoll, 4*sizeof(int)); | 143 | CHECK_SI_SIZE (_sigpoll, 4*sizeof(int)); |
| 91 | 144 | ||
| 145 | BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x10); | ||
| 146 | BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x18); | ||
| 147 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_band) != 0x0C); | ||
| 148 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_fd) != 0x10); | ||
| 149 | |||
| 92 | CHECK_CSI_OFFSET(_sigsys); | 150 | CHECK_CSI_OFFSET(_sigsys); |
| 93 | CHECK_CSI_SIZE (_sigsys, 3*sizeof(int)); | 151 | CHECK_CSI_SIZE (_sigsys, 3*sizeof(int)); |
| 94 | CHECK_SI_SIZE (_sigsys, 4*sizeof(int)); | 152 | CHECK_SI_SIZE (_sigsys, 4*sizeof(int)); |
| 95 | 153 | ||
| 154 | BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x10); | ||
| 155 | BUILD_BUG_ON(offsetof(siginfo_t, si_syscall) != 0x18); | ||
| 156 | BUILD_BUG_ON(offsetof(siginfo_t, si_arch) != 0x1C); | ||
| 157 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_call_addr) != 0x0C); | ||
| 158 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_syscall) != 0x10); | ||
| 159 | BUILD_BUG_ON(offsetof(compat_siginfo_t, si_arch) != 0x14); | ||
| 160 | |||
| 96 | /* any new si_fields should be added here */ | 161 | /* any new si_fields should be added here */ |
| 97 | } | 162 | } |
| 98 | 163 | ||