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commit 3bac39a10abf292d332bb20ab58c6dd5c28f9108
Author: Eugene Syromyatnikov <evgsyr@gmail.com>
Date:   Fri Mar 8 04:07:00 2019 +0100

    include/vki: fix vki_siginfo_t definition on amd64, arm64, and ppc64
    
    As it turned out, the size of vki_siginfo_t is incorrect on these 64-bit
    architectures:
    
        (gdb) p sizeof(vki_siginfo_t)
        $1 = 136
        (gdb) ptype struct vki_siginfo
        type = struct vki_siginfo {
            int si_signo;
            int si_errno;
            int si_code;
            union {
                int _pad[29];
                struct {...} _kill;
                struct {...} _timer;
                struct {...} _rt;
                struct {...} _sigchld;
                struct {...} _sigfault;
                struct {...} _sigpoll;
            } _sifields;
        }
    
    It looks like that for this architecture, __VKI_ARCH_SI_PREAMBLE_SIZE
    hasn't been defined properly, which resulted in incorrect
    VKI_SI_PAD_SIZE calculation (29 instead of 28).
    
        <6a9e4>   DW_AT_name        : (indirect string, offset: 0xcf59): _sifields
        <6a9ef>   DW_AT_data_member_location: 16
    
    This issue has been discovered with strace's "make check-valgrind-memcheck",
    which produced false out-of-bounds writes on ptrace(PTRACE_GETSIGINFO) calls:
    
        SYSCALL[24264,1](101) sys_ptrace ( 16898, 24283, 0x0, 0x606bd40 )
        ==24264== Syscall param ptrace(getsiginfo) points to unaddressable byte(s)
        ==24264==    at 0x575C06E: ptrace (ptrace.c:45)
        ==24264==    by 0x443244: next_event (strace.c:2431)
        ==24264==    by 0x443D30: main (strace.c:2845)
        ==24264==  Address 0x606bdc0 is 0 bytes after a block of size 144 alloc'd
    
    (Note that the address passed is 0x606bd40 and the address reported is
    0x606bdc0).
    
    After the patch, no such errors observed.
    
    * include/vki/vki-amd64-linux.h [__x86_64__ && __ILP32__]
    (__vki_kernel_si_clock_t): New typedef.
    [__x86_64__ && __ILP32__] (__VKI_ARCH_SI_CLOCK_T,
    __VKI_ARCH_SI_ATTRIBUTES): New macros.
    [__x86_64__ && !__ILP32__] (__VKI_ARCH_SI_PREAMBLE_SIZE): New macro,
    define to 4 ints.
    * include/vki/vki-arm64-linux.h (__VKI_ARCH_SI_PREAMBLE_SIZE): Likewise.
    * include/vki/vki-ppc64-linux.h [__powerpc64__] (__VKI_ARCH_SI_PREAMBLE_SIZE):
    Likewise.
    * include/vki/vki-linux.h [!__VKI_ARCH_SI_CLOCK_T]
    (__VKI_ARCH_SI_CLOCK_T): New macro, define to vki_clock_t.
    [!__VKI_ARCH_SI_ATTRIBUTES] (__VKI_ARCH_SI_ATTRIBUTES): New macro,
    define to nil.
    (struct vki_siginfo): Use __VKI_ARCH_SI_CLOCK_T type for _utime and
    _stime fields.  Add __VKI_ARCH_SI_ATTRIBUTES.
    
    Resolves: https://bugs.kde.org/show_bug.cgi?id=405201
    Reported-by: Dmitry V. Levin <ldv@altlinux.org>
    Signed-off-by: Eugene Syromyatnikov <evgsyr@gmail.com>

diff --git a/include/vki/vki-amd64-linux.h b/include/vki/vki-amd64-linux.h
index d6a5a77e6..fbd353aed 100644
--- a/include/vki/vki-amd64-linux.h
+++ b/include/vki/vki-amd64-linux.h
@@ -297,6 +297,21 @@ struct vki_f_owner_ex {
 #define VKI_RLIMIT_CORE		4	/* max core file size */
 #define VKI_RLIMIT_NOFILE	7	/* max number of open files */
 
+//----------------------------------------------------------------------
+// From linux-5.0.0/arch/x86/include/uapi/asm/siginfo.h
+//----------------------------------------------------------------------
+
+/* We need that to ensure that sizeof(siginfo) == 128. */
+#ifdef __x86_64__
+# ifdef __ILP32__
+typedef long long __vki_kernel_si_clock_t __attribute__((aligned(4)));
+#  define __VKI_ARCH_SI_CLOCK_T             __vki_kernel_si_clock_t
+#  define __VKI_ARCH_SI_ATTRIBUTES          __attribute__((aligned(8)))
+# else
+#  define __VKI_ARCH_SI_PREAMBLE_SIZE (4 * sizeof(int))
+# endif
+#endif
+
 //----------------------------------------------------------------------
 // From linux-2.6.9/include/asm-x86_64/socket.h
 //----------------------------------------------------------------------
diff --git a/include/vki/vki-arm64-linux.h b/include/vki/vki-arm64-linux.h
index ecea8cc78..69fb3ed00 100644
--- a/include/vki/vki-arm64-linux.h
+++ b/include/vki/vki-arm64-linux.h
@@ -193,6 +193,12 @@ struct vki_sigcontext {
         __vki_u8 __reserved[4096] __attribute__((__aligned__(16)));
 };
 
+//----------------------------------------------------------------------
+// From linux-5.0.0/arch/arm64/include/uapi/asm/siginfo.h
+//----------------------------------------------------------------------
+
+#define __VKI_ARCH_SI_PREAMBLE_SIZE (4 * sizeof(int))
+
 //----------------------------------------------------------------------
 // From linux-3.10.5/uapi/include/asm-generic/mman-common.h
 //----------------------------------------------------------------------
diff --git a/include/vki/vki-linux.h b/include/vki/vki-linux.h
index 6024f2165..6903c77db 100644
--- a/include/vki/vki-linux.h
+++ b/include/vki/vki-linux.h
@@ -426,6 +426,14 @@ typedef union vki_sigval {
 #define __VKI_ARCH_SI_BAND_T long
 #endif
 
+#ifndef __VKI_ARCH_SI_CLOCK_T
+#define __VKI_ARCH_SI_CLOCK_T vki_clock_t
+#endif
+
+#ifndef __VKI_ARCH_SI_ATTRIBUTES
+#define __VKI_ARCH_SI_ATTRIBUTES
+#endif
+
 // [[Nb: this type changed between 2.4 and 2.6, but not in a way that
 // affects Valgrind.]]
 typedef struct vki_siginfo {
@@ -463,8 +471,8 @@ typedef struct vki_siginfo {
 			vki_pid_t _pid;		/* which child */
 			__VKI_ARCH_SI_UID_T _uid;	/* sender's uid */
 			int _status;		/* exit code */
-			vki_clock_t _utime;
-			vki_clock_t _stime;
+			__VKI_ARCH_SI_CLOCK_T _utime;
+			__VKI_ARCH_SI_CLOCK_T _stime;
 		} _sigchld;
 
 		/* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
@@ -481,7 +489,7 @@ typedef struct vki_siginfo {
 			int _fd;
 		} _sigpoll;
 	} _sifields;
-} vki_siginfo_t;
+} __VKI_ARCH_SI_ATTRIBUTES vki_siginfo_t;
 #endif
 
 #define __VKI_SI_FAULT	0
diff --git a/include/vki/vki-ppc64-linux.h b/include/vki/vki-ppc64-linux.h
index a5e64dd39..04f72048a 100644
--- a/include/vki/vki-ppc64-linux.h
+++ b/include/vki/vki-ppc64-linux.h
@@ -335,6 +335,14 @@ struct vki_sigcontext {
   long             vmx_reserve[VKI_ELF_NVRREG+VKI_ELF_NVRREG+1];
 };
 
+//----------------------------------------------------------------------
+// From linux-5.0.0/arch/powerpc/include/uapi/asm/siginfo.h
+//----------------------------------------------------------------------
+
+#ifdef __powerpc64__
+# define __VKI_ARCH_SI_PREAMBLE_SIZE     (4 * sizeof(int))
+#endif
+
 //----------------------------------------------------------------------
 // From linux-2.6.13/include/asm-ppc64/mman.h
 //----------------------------------------------------------------------