Merge branch 'siginfo-si_trapno-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull siginfo si_trapno updates from Eric Biederman:
 "The full set of si_trapno changes was not appropriate as a fix for the
  newly added SIGTRAP TRAP_PERF, and so I postponed the rest of the
  related cleanups.

  This is the rest of the cleanups for si_trapno that reduces it from
  being a really weird arch special case that is expect to be always
  present (but isn't) on the architectures that support it to being yet
  another field in the _sigfault union of struct siginfo.

  The changes have been reviewed and marinated in linux-next. With the
  removal of this awkward special case new code (like SIGTRAP TRAP_PERF)
  that works across architectures should be easier to write and
  maintain"

* 'siginfo-si_trapno-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signal: Rename SIL_PERF_EVENT SIL_FAULT_PERF_EVENT for consistency
  signal: Verify the alignment and size of siginfo_t
  signal: Remove the generic __ARCH_SI_TRAPNO support
  signal/alpha: si_trapno is only used with SIGFPE and SIGTRAP TRAP_UNK
  signal/sparc: si_trapno is only used with SIGILL ILL_ILLTRP
  arm64: Add compile-time asserts for siginfo_t offsets
  arm: Add compile-time asserts for siginfo_t offsets
  sparc64: Add compile-time asserts for siginfo_t offsets

2 files changed, 78 insertions, 0 deletions

diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 23036334f4dc..1a0e2b56378b 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -1000,3 +1000,42 @@ void __init minsigstksz_setup(void)
 		round_up(sizeof(struct frame_record), 16) +
 		16; /* max alignment padding */
 }
+
+/*
+ * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
+ * changes likely come with new fields that should be added below.
+ */
+static_assert(NSIGILL	== 11);
+static_assert(NSIGFPE	== 15);
+static_assert(NSIGSEGV	== 9);
+static_assert(NSIGBUS	== 5);
+static_assert(NSIGTRAP	== 6);
+static_assert(NSIGCHLD	== 6);
+static_assert(NSIGSYS	== 2);
+static_assert(sizeof(siginfo_t) == 128);
+static_assert(__alignof__(siginfo_t) == 8);
+static_assert(offsetof(siginfo_t, si_signo)	== 0x00);
+static_assert(offsetof(siginfo_t, si_errno)	== 0x04);
+static_assert(offsetof(siginfo_t, si_code)	== 0x08);
+static_assert(offsetof(siginfo_t, si_pid)	== 0x10);
+static_assert(offsetof(siginfo_t, si_uid)	== 0x14);
+static_assert(offsetof(siginfo_t, si_tid)	== 0x10);
+static_assert(offsetof(siginfo_t, si_overrun)	== 0x14);
+static_assert(offsetof(siginfo_t, si_status)	== 0x18);
+static_assert(offsetof(siginfo_t, si_utime)	== 0x20);
+static_assert(offsetof(siginfo_t, si_stime)	== 0x28);
+static_assert(offsetof(siginfo_t, si_value)	== 0x18);
+static_assert(offsetof(siginfo_t, si_int)	== 0x18);
+static_assert(offsetof(siginfo_t, si_ptr)	== 0x18);
+static_assert(offsetof(siginfo_t, si_addr)	== 0x10);
+static_assert(offsetof(siginfo_t, si_addr_lsb)	== 0x18);
+static_assert(offsetof(siginfo_t, si_lower)	== 0x20);
+static_assert(offsetof(siginfo_t, si_upper)	== 0x28);
+static_assert(offsetof(siginfo_t, si_pkey)	== 0x20);
+static_assert(offsetof(siginfo_t, si_perf_data)	== 0x18);
+static_assert(offsetof(siginfo_t, si_perf_type)	== 0x20);
+static_assert(offsetof(siginfo_t, si_band)	== 0x10);
+static_assert(offsetof(siginfo_t, si_fd)	== 0x18);
+static_assert(offsetof(siginfo_t, si_call_addr)	== 0x10);
+static_assert(offsetof(siginfo_t, si_syscall)	== 0x18);
+static_assert(offsetof(siginfo_t, si_arch)	== 0x1c);
diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index 2f507f565c48..d3be01c46bec 100644
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c
@@ -457,3 +457,42 @@ void compat_setup_restart_syscall(struct pt_regs *regs)
 {
        regs->regs[7] = __NR_compat_restart_syscall;
 }
+
+/*
+ * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
+ * changes likely come with new fields that should be added below.
+ */
+static_assert(NSIGILL	== 11);
+static_assert(NSIGFPE	== 15);
+static_assert(NSIGSEGV	== 9);
+static_assert(NSIGBUS	== 5);
+static_assert(NSIGTRAP	== 6);
+static_assert(NSIGCHLD	== 6);
+static_assert(NSIGSYS	== 2);
+static_assert(sizeof(compat_siginfo_t) == 128);
+static_assert(__alignof__(compat_siginfo_t) == 4);
+static_assert(offsetof(compat_siginfo_t, si_signo)	== 0x00);
+static_assert(offsetof(compat_siginfo_t, si_errno)	== 0x04);
+static_assert(offsetof(compat_siginfo_t, si_code)	== 0x08);
+static_assert(offsetof(compat_siginfo_t, si_pid)	== 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_uid)	== 0x10);
+static_assert(offsetof(compat_siginfo_t, si_tid)	== 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_overrun)	== 0x10);
+static_assert(offsetof(compat_siginfo_t, si_status)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_utime)	== 0x18);
+static_assert(offsetof(compat_siginfo_t, si_stime)	== 0x1c);
+static_assert(offsetof(compat_siginfo_t, si_value)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_int)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_ptr)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_addr)	== 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_addr_lsb)	== 0x10);
+static_assert(offsetof(compat_siginfo_t, si_lower)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_upper)	== 0x18);
+static_assert(offsetof(compat_siginfo_t, si_pkey)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_perf_data)	== 0x10);
+static_assert(offsetof(compat_siginfo_t, si_perf_type)	== 0x14);
+static_assert(offsetof(compat_siginfo_t, si_band)	== 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_fd)		== 0x10);
+static_assert(offsetof(compat_siginfo_t, si_call_addr)	== 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_syscall)	== 0x10);
+static_assert(offsetof(compat_siginfo_t, si_arch)	== 0x14);