commit b0861063a8d2a55bb7423e90d26806bab0f78a12

Author: Alexandra Hájková <ahajkova@redhat.com>

Date:   Tue Jun 4 13:47:14 2019 +0200

    Add support for preadv2 and pwritev2 syscalls

    Support for amd64, x86 - 64 and 32 bit, arm64, ppc64, ppc64le,

    s390x, mips64. This should work identically on all

    arches, tested on x86 32bit and 64bit one, but enabled on all.

    Refactor the code to be reusable between old/new syscalls. Resolve TODO

    items in the code. Add the testcase for the preadv2/pwritev2 and also

    add the (similar) testcase for the older preadv/pwritev syscalls.

    Trying to test handling an uninitialized flag argument for the v2 syscalls

    does not work because the flag always comes out as defined zero.

    Turns out glibc does this deliberately on 64bit architectures because

    the kernel does actually have a low_offset and high_offset argument, but

    ignores the high_offset/assumes it is zero.

    https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=601cc11d054ae4b5e9b5babec3d8e4667a2cb9b5

    https://bugs.kde.org/408414

diff --git a/configure.ac b/configure.ac

index 352892565..3596d2fec 100755

--- a/configure.ac

+++ b/configure.ac

@@ -4173,6 +4173,10 @@ AC_CHECK_FUNCS([     \

         process_vm_readv  \

         process_vm_writev \

         copy_file_range \

+        preadv \

+        pwritev \

+        preadv2 \

+        pwritev2 \

         ])

 # AC_CHECK_LIB adds any library found to the variable LIBS, and links these

@@ -4190,6 +4194,10 @@ AM_CONDITIONAL([HAVE_PTHREAD_SETNAME_NP],

                [test x$ac_cv_func_pthread_setname_np = xyes])

 AM_CONDITIONAL([HAVE_COPY_FILE_RANGE],

                [test x$ac_cv_func_copy_file_range = xyes])

+AM_CONDITIONAL([HAVE_PREADV_PWRITEV],

+               [test x$ac_cv_func_preadv = xyes && test x$ac_cv_func_pwritev = xyes])

+AM_CONDITIONAL([HAVE_PREADV2_PWRITEV2],

+               [test x$ac_cv_func_preadv2 = xyes && test x$ac_cv_func_pwritev2 = xyes])

 if test x$VGCONF_PLATFORM_PRI_CAPS = xMIPS32_LINUX \

      -o x$VGCONF_PLATFORM_PRI_CAPS = xMIPS64_LINUX ; then

diff --git a/coregrind/m_syswrap/priv_syswrap-generic.h b/coregrind/m_syswrap/priv_syswrap-generic.h

index 3e1c8b682..73f9224f7 100644

--- a/coregrind/m_syswrap/priv_syswrap-generic.h

+++ b/coregrind/m_syswrap/priv_syswrap-generic.h

@@ -109,6 +109,19 @@ ML_(handle_auxv_open)(SyscallStatus *status, const HChar *filename,

 /* Helper function for generic mprotect and linux pkey_mprotect. */

 extern void handle_sys_mprotect (ThreadId tid, SyscallStatus *status,

                                  Addr *addr, SizeT *len, Int *prot);

+/* Helper functions for preadv/preadv2. */

+extern

+void handle_pre_sys_preadv(ThreadId tid, SyscallStatus* status,

+                           Int fd, Addr vector, Int count,

+                           const char *str);

+extern

+void handle_post_sys_preadv(ThreadId tid, SyscallStatus* status, Addr vector, Int count);

+

+/* Helper function for pwritev/pwritev2. */

+extern

+void handle_sys_pwritev(ThreadId tid, SyscallStatus* status,

+                        Int fd, Addr vector, Int count,

+                        const char *str);

 DECL_TEMPLATE(generic, sys_ni_syscall);            // * P -- unimplemented

 DECL_TEMPLATE(generic, sys_exit);

diff --git a/coregrind/m_syswrap/priv_syswrap-linux.h b/coregrind/m_syswrap/priv_syswrap-linux.h

index be2f9bdde..8ce8ef3d5 100644

--- a/coregrind/m_syswrap/priv_syswrap-linux.h

+++ b/coregrind/m_syswrap/priv_syswrap-linux.h

@@ -46,7 +46,9 @@ DECL_TEMPLATE(linux, sys_oldumount);

 DECL_TEMPLATE(linux, sys_umount);

 DECL_TEMPLATE(linux, sys_perf_event_open);

 DECL_TEMPLATE(linux, sys_preadv);

+DECL_TEMPLATE(linux, sys_preadv2);

 DECL_TEMPLATE(linux, sys_pwritev);

+DECL_TEMPLATE(linux, sys_pwritev2);

 DECL_TEMPLATE(linux, sys_sendmmsg);

 DECL_TEMPLATE(linux, sys_recvmmsg);

 DECL_TEMPLATE(linux, sys_dup3);

diff --git a/coregrind/m_syswrap/syswrap-amd64-linux.c b/coregrind/m_syswrap/syswrap-amd64-linux.c

index 382dc65cf..9b8068d0f 100644

--- a/coregrind/m_syswrap/syswrap-amd64-linux.c

+++ b/coregrind/m_syswrap/syswrap-amd64-linux.c

@@ -857,6 +857,8 @@ static SyscallTableEntry syscall_table[] = {

 //   LIN__(__NR_kexec_file_load,   sys_ni_syscall),       // 320

    LINXY(__NR_bpf,               sys_bpf),              // 321

+   LINXY(__NR_preadv2,           sys_preadv2),           // 327

+   LINX_(__NR_pwritev2,          sys_pwritev2),          // 328

    LINXY(__NR_statx,             sys_statx),             // 332

diff --git a/coregrind/m_syswrap/syswrap-arm64-linux.c b/coregrind/m_syswrap/syswrap-arm64-linux.c

index c700e3dbe..d12d40632 100644

--- a/coregrind/m_syswrap/syswrap-arm64-linux.c

+++ b/coregrind/m_syswrap/syswrap-arm64-linux.c

@@ -818,8 +818,8 @@ static SyscallTableEntry syscall_main_table[] = {

    LINX_(__NR_membarrier,        sys_membarrier),        // 283

    //   (__NR_mlock2,            sys_ni_syscall),        // 284

    LINX_(__NR_copy_file_range,   sys_copy_file_range),   // 285

-   //   (__NR_preadv2,           sys_ni_syscall),        // 286

-   //   (__NR_pwritev2,          sys_ni_syscall),        // 287

+   LINX_(__NR_preadv2,           sys_ni_syscall),        // 286

+   LINX_(__NR_pwritev2,          sys_ni_syscall),        // 287

    //   (__NR_pkey_mprotect,     sys_ni_syscall),        // 288

    //   (__NR_pkey_alloc,        sys_ni_syscall),        // 289

    //   (__NR_pkey_free,         sys_ni_syscall),        // 290

diff --git a/coregrind/m_syswrap/syswrap-linux.c b/coregrind/m_syswrap/syswrap-linux.c

index 36d09d6e0..2fe15d97b 100644

--- a/coregrind/m_syswrap/syswrap-linux.c

+++ b/coregrind/m_syswrap/syswrap-linux.c

@@ -5501,12 +5501,57 @@ POST(sys_open_by_handle_at)

 /* ---------------------------------------------------------------------

    p{read,write}v wrappers

    ------------------------------------------------------------------ */

+/* This handles the common part of the PRE macro for preadv and preadv2. */

+void handle_pre_sys_preadv(ThreadId tid, SyscallStatus* status,

+                           Int fd, Addr vector, Int count, const char *str)

+{

+   struct vki_iovec * vec;

+   Int i;

+   /* safe size for the "preadv/preadv2(vector[i])" string */

+   char tmp[30];

+

+   if (!ML_(fd_allowed)(fd, str, tid, False)) {

+      SET_STATUS_Failure( VKI_EBADF );

+   } else if (count > 0) {

+      VG_(strcpy) (tmp, str);

+      VG_(strcat) (tmp, "(vector)");

+      PRE_MEM_READ( tmp, vector, count * sizeof(struct vki_iovec) );

+

+      if (ML_(safe_to_deref) ((void *)(Addr)vector,

+                              count * sizeof(struct vki_iovec))) {

+         vec = (struct vki_iovec *)(Addr)vector;

+         for (i = 0; i < count; i++) {

+            VG_(snprintf) (tmp, 30, "%s(vector[%d])", str, i);

+            PRE_MEM_WRITE( tmp, (Addr)vec[i].iov_base, vec[i].iov_len );

+         }

+      }

+   }

+}

+

+/* This handles the common part of the POST macro for preadv and preadv2. */

+void handle_post_sys_preadv(ThreadId tid, SyscallStatus* status, Addr vector, Int count)

+{

+    vg_assert(SUCCESS);

+    if (RES > 0) {

+        Int i;

+        struct vki_iovec * vec = (struct vki_iovec *)(Addr)vector;

+        Int remains = RES;

+

+        /* RES holds the number of bytes read. */

+        for (i = 0; i < count; i++) {

+            Int nReadThisBuf = vec[i].iov_len;

+            if (nReadThisBuf > remains) nReadThisBuf = remains;

+            POST_MEM_WRITE( (Addr)vec[i].iov_base, nReadThisBuf );

+            remains -= nReadThisBuf;

+            if (remains < 0) VG_(core_panic)("preadv: remains < 0");

+        }

+    }

+}

 PRE(sys_preadv)

 {

-   Int i;

-   struct vki_iovec * vec;

    *flags |= SfMayBlock;

+   const char *str = "preadv";

 #if VG_WORDSIZE == 4

    /* Note that the offset argument here is in lo+hi order on both

       big and little endian platforms... */

@@ -5525,45 +5570,89 @@ PRE(sys_preadv)

 #else

 #  error Unexpected word size

 #endif

-   if (!ML_(fd_allowed)(ARG1, "preadv", tid, False)) {

-      SET_STATUS_Failure( VKI_EBADF );

-   } else {

-      PRE_MEM_READ( "preadv(vector)", ARG2, ARG3 * sizeof(struct vki_iovec) );

+   Int fd = ARG1;

+   Addr vector = ARG2;

+   Int count = ARG3;

+

+   handle_pre_sys_preadv(tid, status, fd, vector, count, str);

-      if (ARG2 != 0) {

-         /* ToDo: don't do any of the following if the vector is invalid */

-         vec = (struct vki_iovec *)(Addr)ARG2;

-         for (i = 0; i < (Int)ARG3; i++)

-            PRE_MEM_WRITE( "preadv(vector[...])",

-                           (Addr)vec[i].iov_base, vec[i].iov_len );

-      }

-   }

 }

 POST(sys_preadv)

 {

-   vg_assert(SUCCESS);

-   if (RES > 0) {

-      Int i;

-      struct vki_iovec * vec = (struct vki_iovec *)(Addr)ARG2;

-      Int remains = RES;

+   Addr vector = ARG2;

+   Int count = ARG3;

-      /* RES holds the number of bytes read. */

-      for (i = 0; i < (Int)ARG3; i++) {

-	 Int nReadThisBuf = vec[i].iov_len;

-	 if (nReadThisBuf > remains) nReadThisBuf = remains;

-	 POST_MEM_WRITE( (Addr)vec[i].iov_base, nReadThisBuf );

-	 remains -= nReadThisBuf;

-	 if (remains < 0) VG_(core_panic)("preadv: remains < 0");

+   handle_post_sys_preadv(tid, status, vector, count);

+}

+

+PRE(sys_preadv2)

+{

+   *flags |= SfMayBlock;

+   const char *str = "preadv2";

+#if VG_WORDSIZE == 4

+   /* Note that the offset argument here is in lo+hi order on both

+      big and little endian platforms... */

+   PRINT("sys_preadv2 ( %" FMT_REGWORD "u, %#" FMT_REGWORD "x, %" FMT_REGWORD

+         "u, %lld, %" FMT_REGWORD "u )",

+         ARG1, ARG2, ARG3, (Long)LOHI64(ARG4,ARG5), ARG6);

+   PRE_REG_READ6(ssize_t, "preadv2",

+                 unsigned long, fd, const struct iovec *, vector,

+                 unsigned long, count, vki_u32, offset_low,

+                 vki_u32, offset_high, unsigned long, flags);

+#elif VG_WORDSIZE == 8

+   PRINT("sys_preadv2 ( %lu, %#lx, %lu, %ld, %lu )", ARG1, ARG2, ARG3, SARG4, ARG5);

+   PRE_REG_READ5(ssize_t, "preadv2",

+                 unsigned long, fd, const struct iovec *, vector,

+                 unsigned long, count, Word, offset, unsigned long, flags);

+#else

+#  error Unexpected word size

+#endif

+   Int fd = ARG1;

+   Addr vector = ARG2;

+   Int count = ARG3;

+

+   handle_pre_sys_preadv(tid, status, fd, vector, count, str);

+}

+

+POST(sys_preadv2)

+{

+   Addr vector = ARG2;

+   Int count = ARG3;

+

+   handle_post_sys_preadv(tid, status, vector, count);

+}

+

+/* This handles the common part of the PRE macro for pwritev and pwritev2. */

+void handle_sys_pwritev(ThreadId tid, SyscallStatus* status,

+                        Int fd, Addr vector, Int count, const char *str)

+{

+   Int i;

+   struct vki_iovec * vec;

+   /* safe size for the "preadv/preadv2(vector[i])" string */

+   char tmp[30];

+

+   if (!ML_(fd_allowed)(fd, str, tid, False)) {

+      SET_STATUS_Failure( VKI_EBADF );

+   } else if (count > 0) {

+      VG_(strcpy) (tmp, str);

+      VG_(strcat) (tmp, "(vector)");

+      PRE_MEM_READ( tmp, vector, count * sizeof(struct vki_iovec) );

+      if (ML_(safe_to_deref) ((void *)(Addr)vector,

+                              count * sizeof(struct vki_iovec))) {

+         vec = (struct vki_iovec *)(Addr)vector;

+         for (i = 0; i < count; i++) {

+            VG_(snprintf) (tmp, 30, "%s(vector[%d])", str, i);

+            PRE_MEM_READ( tmp, (Addr)vec[i].iov_base, vec[i].iov_len );

+         }

       }

    }

 }

 PRE(sys_pwritev)

 {

-   Int i;

-   struct vki_iovec * vec;

    *flags |= SfMayBlock;

+   const char *str = "pwritev";

 #if VG_WORDSIZE == 4

    /* Note that the offset argument here is in lo+hi order on both

       big and little endian platforms... */

@@ -5581,19 +5670,41 @@ PRE(sys_pwritev)

 #else

 #  error Unexpected word size

 #endif

-   if (!ML_(fd_allowed)(ARG1, "pwritev", tid, False)) {

-      SET_STATUS_Failure( VKI_EBADF );

-   } else {

-      PRE_MEM_READ( "pwritev(vector)", 

-		     ARG2, ARG3 * sizeof(struct vki_iovec) );

-      if (ARG2 != 0) {

-         /* ToDo: don't do any of the following if the vector is invalid */

-         vec = (struct vki_iovec *)(Addr)ARG2;

-         for (i = 0; i < (Int)ARG3; i++)

-            PRE_MEM_READ( "pwritev(vector[...])",

-                           (Addr)vec[i].iov_base, vec[i].iov_len );

-      }

-   }

+   Int fd = ARG1;

+   Addr vector = ARG2;

+   Int count = ARG3;

+

+   handle_sys_pwritev(tid, status, fd, vector, count, str);

+}

+

+PRE(sys_pwritev2)

+{

+   *flags |= SfMayBlock;

+   const char *str = "pwritev2";

+#if VG_WORDSIZE == 4

+   /* Note that the offset argument here is in lo+hi order on both

+      big and little endian platforms... */

+   PRINT("sys_pwritev2 ( %" FMT_REGWORD "u, %#" FMT_REGWORD "x, %" FMT_REGWORD

+         "u, %lld, %" FMT_REGWORD "u )",

+         ARG1, ARG2, ARG3, (Long)LOHI64(ARG4,ARG5), ARG6);

+   PRE_REG_READ6(ssize_t, "pwritev2",

+                 unsigned long, fd, const struct iovec *, vector,

+                 unsigned long, count, vki_u32, offset_low,

+                 vki_u32, offset_high, unsigned long, flags);

+#elif VG_WORDSIZE == 8

+   /* Note offset_high isn't actually used?  */

+   PRE_REG_READ6(ssize_t, "pwritev2",

+                 unsigned long, fd, const struct iovec *, vector,

+                 unsigned long, count, Word, offset,

+		 Word, offset_high, unsigned long, flags);

+#else

+#  error Unexpected word size

+#endif

+   Int fd = ARG1;

+   Addr vector = ARG2;

+   Int count = ARG3;

+

+   handle_sys_pwritev(tid, status, fd, vector, count, str);

 }

 /* ---------------------------------------------------------------------

diff --git a/coregrind/m_syswrap/syswrap-ppc64-linux.c b/coregrind/m_syswrap/syswrap-ppc64-linux.c

index baa2934ab..d65a664dd 100644

--- a/coregrind/m_syswrap/syswrap-ppc64-linux.c

+++ b/coregrind/m_syswrap/syswrap-ppc64-linux.c

@@ -1006,6 +1006,8 @@ static SyscallTableEntry syscall_table[] = {

    LINX_(__NR_membarrier,        sys_membarrier),       // 365

    LINX_(__NR_copy_file_range,   sys_copy_file_range),  // 379

+   LINX_(__NR_preadv2,           sys_preadv2),          // 380

+   LINX_(__NR_pwritev2,          sys_pwritev2),         // 381

    LINXY(__NR_statx,             sys_statx),            // 383

 };

diff --git a/coregrind/m_syswrap/syswrap-s390x-linux.c b/coregrind/m_syswrap/syswrap-s390x-linux.c

index 1481e768b..3354d41c0 100644

--- a/coregrind/m_syswrap/syswrap-s390x-linux.c

+++ b/coregrind/m_syswrap/syswrap-s390x-linux.c

@@ -853,6 +853,8 @@ static SyscallTableEntry syscall_table[] = {

    LINX_(__NR_shutdown, sys_shutdown),                                // 373

    LINX_(__NR_copy_file_range, sys_copy_file_range),                  // 375

+   LINXY(__NR_preadv2, sys_preadv2),                                  // 376

+   LINX_(__NR_pwritev2, sys_pwritev2),                                // 377

    LINXY(__NR_statx, sys_statx),                                      // 379

 };

diff --git a/coregrind/m_syswrap/syswrap-x86-linux.c b/coregrind/m_syswrap/syswrap-x86-linux.c

index 9ff53a92a..33d1213a3 100644

--- a/coregrind/m_syswrap/syswrap-x86-linux.c

+++ b/coregrind/m_syswrap/syswrap-x86-linux.c

@@ -1607,6 +1607,8 @@ static SyscallTableEntry syscall_table[] = {

    LINX_(__NR_membarrier,        sys_membarrier),       // 375

    LINX_(__NR_copy_file_range,   sys_copy_file_range),   // 377

+   LINXY(__NR_preadv2,           sys_preadv2),           // 378

+   LINX_(__NR_pwritev2,          sys_pwritev2),          // 379

    LINXY(__NR_pkey_mprotect,     sys_pkey_mprotect),    // 380

    LINX_(__NR_pkey_alloc,        sys_pkey_alloc),       // 381

diff --git a/memcheck/tests/linux/Makefile.am b/memcheck/tests/linux/Makefile.am

index 00e99a52a..e13325869 100644

--- a/memcheck/tests/linux/Makefile.am

+++ b/memcheck/tests/linux/Makefile.am

@@ -26,7 +26,9 @@ EXTRA_DIST = \

 	timerfd-syscall.vgtest timerfd-syscall.stderr.exp \

 	with-space.stderr.exp with-space.stdout.exp with-space.vgtest \

 	proc-auxv.vgtest proc-auxv.stderr.exp getregset.vgtest \

-	getregset.stderr.exp getregset.stdout.exp

+	getregset.stderr.exp getregset.stdout.exp \

+	sys-preadv_pwritev.vgtest sys-preadv_pwritev.stderr.exp \

+	sys-preadv2_pwritev2.vgtest sys-preadv2_pwritev2.stderr.exp

 check_PROGRAMS = \

 	brk \

@@ -54,6 +56,14 @@ if HAVE_COPY_FILE_RANGE

         check_PROGRAMS += sys-copy_file_range

 endif

+if HAVE_PREADV_PWRITEV

+        check_PROGRAMS += sys-preadv_pwritev

+endif

+

+if HAVE_PREADV2_PWRITEV2

+        check_PROGRAMS += sys-preadv2_pwritev2

+endif

+

 AM_CFLAGS   += $(AM_FLAG_M3264_PRI)

 AM_CXXFLAGS += $(AM_FLAG_M3264_PRI)

diff --git a/memcheck/tests/linux/sys-preadv2_pwritev2.c b/memcheck/tests/linux/sys-preadv2_pwritev2.c

new file mode 100644

index 000000000..942eab68b

--- /dev/null

+++ b/memcheck/tests/linux/sys-preadv2_pwritev2.c

@@ -0,0 +1,79 @@

+#define _GNU_SOURCE

+#include <fcntl.h>

+#include <stdio.h>

+#include <stdlib.h>

+#include <sys/stat.h>

+#include <unistd.h>

+#include <sys/syscall.h>

+#include <sys/uio.h>

+#include <string.h>

+#include "../../memcheck.h"

+

+#include <errno.h>

+

+int main(int argc, char **argv)

+{

+    char str0[] = "hello ";

+    char str1[] = "world\n";

+    struct iovec iov[2];

+    int fd;

+

+    fd = open("prwv2_source", O_CREAT | O_RDWR, 0644);

+    if (fd == -1) {

+        perror("prwv2_source");

+        exit(EXIT_FAILURE);

+    }

+

+    iov[0].iov_base = str0;

+    iov[0].iov_len = strlen(str0);

+    iov[1].iov_base = str1;

+    iov[1].iov_len = strlen(str1);

+

+    /* Check pwritev2 and preadv2 called with the correct arguments works. */

+    if (pwritev2(fd, iov, 2, 0, 0) == -1) {

+        perror("pwritev2");

+        exit(EXIT_FAILURE);

+    }

+

+    if (preadv2(fd, iov, 2, 0, 0) == -1) {

+        perror("preadv2");

+        printf("errno: %d\n", errno);

+        exit(EXIT_FAILURE);

+    }

+

+    /* Check valgrind will produce expected warnings for the

+       various wrong arguments. */

+    do {

+        /* always allocate 16 bytes to not to have different .exps for different reg sizes */

+        char *mem = malloc(16);

+        void *t = (void *) &mem[0];

+        void *z = (void *) -1;

+	int c = *((int *) &mem[4]);

+        int flag = *((int *) &mem[8]);

+        pwritev2(fd, NULL, 2, 0, 0);

+        pwritev2(fd, z, 2, 0, 0);

+        pwritev2(fd, t, 2, 0, 0);

+        pwritev2(fd, iov, -1, 0, 0);

+        pwritev2(fd, iov, c, 0, 0);

+        pwritev2(fd, iov, 2, -5, 0);

+        pwritev2(-1, iov, 2, -5, 0);

+        pwritev2(fd, iov, 2, -5, flag);

+

+        preadv2(fd, NULL, 2, 0, 0);

+        preadv2(fd, z, 2, 0, 0);

+        preadv2(fd, t, 2, 0, 0);

+        preadv2(fd, iov, -1, 0, 0);

+        preadv2(fd, iov, c, 0, 0);

+        preadv2(fd, iov, 2, -5, 0);

+        preadv2(-1, iov, 2, -5, 0);

+

+        iov[1].iov_base = (void *) -1;

+        pwritev2(fd, iov, 2, 0, 0);

+        preadv2(fd, iov, 2, 0, 0);

+        free(mem);

+    } while (0);

+

+    close(fd);

+    unlink("prwv2_source");

+    exit(EXIT_SUCCESS);

+}

diff --git a/memcheck/tests/linux/sys-preadv2_pwritev2.stderr.exp b/memcheck/tests/linux/sys-preadv2_pwritev2.stderr.exp

new file mode 100644

index 000000000..e11f2a51d

--- /dev/null

+++ b/memcheck/tests/linux/sys-preadv2_pwritev2.stderr.exp

@@ -0,0 +1,56 @@

+Syscall param pwritev2(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:53)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param pwritev2(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:54)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param pwritev2(vector) points to uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:55)

+ Address 0x........ is 0 bytes inside a block of size 16 alloc'd

+   at 0x........: malloc (vg_replace_malloc.c:...)

+   by 0x........: main (sys-preadv2_pwritev2.c:48)

+

+Syscall param pwritev2(count) contains uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:57)

+

+Syscall param pwritev2(flags) contains uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:60)

+

+Syscall param preadv2(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:62)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param preadv2(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:63)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param preadv2(vector) points to uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:64)

+ Address 0x........ is 0 bytes inside a block of size 16 alloc'd

+   at 0x........: malloc (vg_replace_malloc.c:...)

+   by 0x........: main (sys-preadv2_pwritev2.c:48)

+

+Syscall param preadv2(count) contains uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:66)

+

+Syscall param pwritev2(vector[1]) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:71)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param preadv2(vector[1]) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv2_pwritev2.c:72)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

diff --git a/memcheck/tests/linux/sys-preadv2_pwritev2.vgtest b/memcheck/tests/linux/sys-preadv2_pwritev2.vgtest

new file mode 100644

index 000000000..5cd23aacd

--- /dev/null

+++ b/memcheck/tests/linux/sys-preadv2_pwritev2.vgtest

@@ -0,0 +1,3 @@

+prereq: test -e sys-preadv2_pwritev2

+prog: sys-preadv2_pwritev2

+vgopts: -q

diff --git a/memcheck/tests/linux/sys-preadv_pwritev.c b/memcheck/tests/linux/sys-preadv_pwritev.c

new file mode 100644

index 000000000..f5087dddc

--- /dev/null

+++ b/memcheck/tests/linux/sys-preadv_pwritev.c

@@ -0,0 +1,77 @@

+#define _GNU_SOURCE

+#include <fcntl.h>

+#include <stdio.h>

+#include <stdlib.h>

+#include <sys/stat.h>

+#include <unistd.h>

+#include <sys/syscall.h>

+#include <sys/uio.h>

+#include <string.h>

+#include "../../memcheck.h"

+

+#include <errno.h>

+

+int main(int argc, char **argv)

+{

+    char str0[] = "hello ";

+    char str1[] = "world\n";

+    struct iovec iov[2];

+    int fd;

+

+    fd = open("prwv_source", O_CREAT | O_RDWR, 0644);

+    if (fd == -1) {

+        perror("prwv2_source");

+        exit(EXIT_FAILURE);

+    }

+

+    iov[0].iov_base = str0;

+    iov[0].iov_len = strlen(str0);

+    iov[1].iov_base = str1;

+    iov[1].iov_len = strlen(str1);

+

+    /* Check pwritev and preadv called with the correct arguments works. */

+    if (pwritev(fd, iov, 2, 0) == -1) {

+        perror("pwritev");

+        exit(EXIT_FAILURE);

+    }

+

+    if (preadv(fd, iov, 2, 0) == -1) {

+        perror("preadv");

+        printf("errno: %d\n", errno);

+        exit(EXIT_FAILURE);

+    }

+

+    /* Check valgrind will produce expected warnings for the

+       various wrong arguments. */

+    do {

+        /* always allocate 16 bytes to not to have different .exps for different reg sizes */

+        char *mem = malloc(16);

+        void *t = (void *) &mem[0];

+        void *z = (void *) -1;

+        int c = *((int *) &mem[4]);

+        pwritev(fd, NULL, 2, 0);

+        pwritev(fd, z, 2, 0);

+        pwritev(fd, t, 2, 0);

+        pwritev(fd, iov, -1, 0);

+        pwritev(fd, iov, c, 0);

+        pwritev(fd, iov, 2, -5);

+        pwritev(-1, iov, 2, -5);

+

+        preadv(fd, NULL, 2, 0);

+        preadv(fd, z, 2, 0);

+        preadv(fd, t, 2, 0);

+        preadv(fd, iov, -1, 0);

+        preadv(fd, iov, c, 0);

+        preadv(fd, iov, 2, -5);

+        preadv(-1, iov, 2, -5);

+

+        iov[1].iov_base = (void *) -1;

+        pwritev(fd, iov, 2, 0);

+        preadv(fd, iov, 2, 0);

+        free(mem);

+    } while (0);

+

+    close(fd);

+    unlink("prwv_source");

+    exit(EXIT_SUCCESS);

+}

diff --git a/memcheck/tests/linux/sys-preadv_pwritev.stderr.exp b/memcheck/tests/linux/sys-preadv_pwritev.stderr.exp

new file mode 100644

index 000000000..4fede44d8

--- /dev/null

+++ b/memcheck/tests/linux/sys-preadv_pwritev.stderr.exp

@@ -0,0 +1,52 @@

+Syscall param pwritev(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:52)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param pwritev(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:53)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param pwritev(vector) points to uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:54)

+ Address 0x........ is 0 bytes inside a block of size 16 alloc'd

+   at 0x........: malloc (vg_replace_malloc.c:...)

+   by 0x........: main (sys-preadv_pwritev.c:48)

+

+Syscall param pwritev(count) contains uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:56)

+

+Syscall param preadv(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:60)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param preadv(vector) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:61)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param preadv(vector) points to uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:62)

+ Address 0x........ is 0 bytes inside a block of size 16 alloc'd

+   at 0x........: malloc (vg_replace_malloc.c:...)

+   by 0x........: main (sys-preadv_pwritev.c:48)

+

+Syscall param preadv(count) contains uninitialised byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:64)

+

+Syscall param pwritev(vector[1]) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:69)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

+Syscall param preadv(vector[1]) points to unaddressable byte(s)

+   ...

+   by 0x........: main (sys-preadv_pwritev.c:70)

+ Address 0x........ is not stack'd, malloc'd or (recently) free'd

+

diff --git a/memcheck/tests/linux/sys-preadv_pwritev.vgtest b/memcheck/tests/linux/sys-preadv_pwritev.vgtest

new file mode 100644

index 000000000..f07dc2935

--- /dev/null