lkml.org 
[lkml]   [2021]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Date
    Subject[PATCH 3/6] arm64: Add compile-time asserts for siginfo_t offsets
    From: Marco Elver <elver@google.com>

    To help catch ABI breaks at compile-time, add compile-time assertions to
    verify the siginfo_t layout.

    Link: https://lkml.kernel.org/r/20210505141101.11519-3-ebiederm@xmission.com
    Link: https://lkml.kernel.org/r/20210429190734.624918-3-elver@google.com
    Signed-off-by: Marco Elver <elver@google.com>
    Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
    ---
    arch/arm64/kernel/signal.c | 37 ++++++++++++++++++++++++++++++++++++
    arch/arm64/kernel/signal32.c | 37 ++++++++++++++++++++++++++++++++++++
    2 files changed, 74 insertions(+)

    diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
    index f8192f4ae0b8..4413b6a4e32a 100644
    --- a/arch/arm64/kernel/signal.c
    +++ b/arch/arm64/kernel/signal.c
    @@ -999,3 +999,40 @@ 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(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..ab1775216712 100644
    --- a/arch/arm64/kernel/signal32.c
    +++ b/arch/arm64/kernel/signal32.c
    @@ -457,3 +457,40 @@ 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(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);
    --
    2.20.1
    \
     
     \ /
      Last update: 2021-07-15 20:12    [W:2.841 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site