]> granicus.if.org Git - strace/blobdiff - io.c
Refactor tamper_with_syscall_exiting()
[strace] / io.c
diff --git a/io.c b/io.c
index 3c4ef592f1d376c3f176ad8a8cbbf778040c7083..cd803057b32131931eab75decbcb7ae9809f2a61 100644 (file)
--- a/io.c
+++ b/io.c
@@ -3,6 +3,7 @@
  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
  * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
+ * Copyright (c) 1999-2018 The strace developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -41,8 +42,8 @@ SYS_FUNC(read)
                if (syserror(tcp))
                        printaddr(tcp->u_arg[1]);
                else
-                       printstr(tcp, tcp->u_arg[1], tcp->u_rval);
-               tprintf(", %lu", tcp->u_arg[2]);
+                       printstrn(tcp, tcp->u_arg[1], tcp->u_rval);
+               tprintf(", %" PRI_klu, tcp->u_arg[2]);
        }
        return 0;
 }
@@ -51,25 +52,25 @@ SYS_FUNC(write)
 {
        printfd(tcp, tcp->u_arg[0]);
        tprints(", ");
-       printstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
-       tprintf(", %lu", tcp->u_arg[2]);
+       printstrn(tcp, tcp->u_arg[1], tcp->u_arg[2]);
+       tprintf(", %" PRI_klu, tcp->u_arg[2]);
 
        return RVAL_DECODED;
 }
 
 struct print_iovec_config {
-       int decode_iov;
-       unsigned long data_size;
+       enum iov_decode decode_iov;
+       kernel_ulong_t data_size;
 };
 
 static bool
 print_iovec(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
 {
-       const unsigned long *iov;
-       unsigned long iov_buf[2];
+       const kernel_ulong_t *iov;
+       kernel_ulong_t iov_buf[2], len;
        struct print_iovec_config *c = data;
 
-        if (elem_size < sizeof(iov_buf)) {
+       if (elem_size < sizeof(iov_buf)) {
                iov_buf[0] = ((unsigned int *) elem_buf)[0];
                iov_buf[1] = ((unsigned int *) elem_buf)[1];
                iov = iov_buf;
@@ -77,19 +78,32 @@ print_iovec(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
                iov = elem_buf;
        }
 
-       tprints("{");
-
-       if (c->decode_iov) {
-               unsigned long len = iov[1];
-               if (len > c->data_size)
-                       len = c->data_size;
-               c->data_size -= len;
-               printstr(tcp, iov[0], len);
-       } else {
-               printaddr(iov[0]);
+       tprints("{iov_base=");
+
+       len = iov[1];
+
+       switch (c->decode_iov) {
+               case IOV_DECODE_STR:
+                       if (len > c->data_size)
+                               len = c->data_size;
+                       if (c->data_size != (kernel_ulong_t) -1)
+                               c->data_size -= len;
+                       printstrn(tcp, iov[0], len);
+                       break;
+               case IOV_DECODE_NETLINK:
+                       if (len > c->data_size)
+                               len = c->data_size;
+                       if (c->data_size != (kernel_ulong_t) -1)
+                               c->data_size -= len;
+                       /* assume that the descriptor is 1st syscall argument */
+                       decode_netlink(tcp, tcp->u_arg[0], iov[0], len);
+                       break;
+               default:
+                       printaddr(iov[0]);
+                       break;
        }
 
-       tprintf(", %lu}", iov[1]);
+       tprintf(", iov_len=%" PRI_klu "}", iov[1]);
 
        return true;
 }
@@ -99,21 +113,17 @@ print_iovec(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
  * Example: recvmsg returing a short read.
  */
 void
-tprint_iov_upto(struct tcb *tcp, unsigned long len, unsigned long addr,
-               int decode_iov, unsigned long data_size)
+tprint_iov_upto(struct tcb *const tcp, const kernel_ulong_t len,
+               const kernel_ulong_t addr, const enum iov_decode decode_iov,
+               const kernel_ulong_t data_size)
 {
-       unsigned long iov[2];
-       struct print_iovec_config config =
-               { .decode_iov = decode_iov, .data_size = data_size };
+       kernel_ulong_t iov[2];
+       struct print_iovec_config config = {
+               .decode_iov = decode_iov, .data_size = data_size
+       };
 
        print_array(tcp, addr, len, iov, current_wordsize * 2,
-                   umoven_or_printaddr, print_iovec, &config);
-}
-
-void
-tprint_iov(struct tcb *tcp, unsigned long len, unsigned long addr, int decode_iov)
-{
-       tprint_iov_upto(tcp, len, addr, decode_iov, (unsigned long) -1L);
+                   tfetch_mem_ignore_syserror, print_iovec, &config);
 }
 
 SYS_FUNC(readv)
@@ -122,9 +132,10 @@ SYS_FUNC(readv)
                printfd(tcp, tcp->u_arg[0]);
                tprints(", ");
        } else {
-               tprint_iov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1], 1,
-                               tcp->u_rval);
-               tprintf(", %lu", tcp->u_arg[2]);
+               tprint_iov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1],
+                               syserror(tcp) ? IOV_DECODE_ADDR :
+                               IOV_DECODE_STR, tcp->u_rval);
+               tprintf(", %" PRI_klu, tcp->u_arg[2]);
        }
        return 0;
 }
@@ -133,23 +144,12 @@ SYS_FUNC(writev)
 {
        printfd(tcp, tcp->u_arg[0]);
        tprints(", ");
-       tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
-       tprintf(", %lu", tcp->u_arg[2]);
+       tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], IOV_DECODE_STR);
+       tprintf(", %" PRI_klu, tcp->u_arg[2]);
 
        return RVAL_DECODED;
 }
 
-/* The SH4 ABI does allow long longs in odd-numbered registers, but
-   does not allow them to be split between registers and memory - and
-   there are only four argument registers for normal functions.  As a
-   result pread takes an extra padding argument before the offset.  This
-   was changed late in the 2.4 series (around 2.4.20).  */
-#if defined(SH)
-#define PREAD_OFFSET_ARG 4
-#else
-#define PREAD_OFFSET_ARG 3
-#endif
-
 SYS_FUNC(pread)
 {
        if (entering(tcp)) {
@@ -159,9 +159,9 @@ SYS_FUNC(pread)
                if (syserror(tcp))
                        printaddr(tcp->u_arg[1]);
                else
-                       printstr(tcp, tcp->u_arg[1], tcp->u_rval);
-               tprintf(", %lu, ", tcp->u_arg[2]);
-               printllval(tcp, "%lld", PREAD_OFFSET_ARG);
+                       printstrn(tcp, tcp->u_arg[1], tcp->u_rval);
+               tprintf(", %" PRI_klu ", ", tcp->u_arg[2]);
+               printllval(tcp, "%lld", 3);
        }
        return 0;
 }
@@ -170,9 +170,9 @@ SYS_FUNC(pwrite)
 {
        printfd(tcp, tcp->u_arg[0]);
        tprints(", ");
-       printstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
-       tprintf(", %lu, ", tcp->u_arg[2]);
-       printllval(tcp, "%lld", PREAD_OFFSET_ARG);
+       printstrn(tcp, tcp->u_arg[1], tcp->u_arg[2]);
+       tprintf(", %" PRI_klu ", ", tcp->u_arg[2]);
+       printllval(tcp, "%lld", 3);
 
        return RVAL_DECODED;
 }
@@ -180,30 +180,20 @@ SYS_FUNC(pwrite)
 static void
 print_lld_from_low_high_val(struct tcb *tcp, int arg)
 {
-#if SIZEOF_LONG == SIZEOF_LONG_LONG
-# if SUPPORTED_PERSONALITIES > 1
-#  ifdef X86_64
-       if (current_personality != 1)
-#  else
-       if (current_wordsize == sizeof(long))
-#  endif
-# endif
-               tprintf("%ld", tcp->u_arg[arg]);
-# if SUPPORTED_PERSONALITIES > 1
-       else
-               tprintf("%ld",
-                       ((unsigned long) tcp->u_arg[arg + 1] << current_wordsize * 8)
-                       | (unsigned long) tcp->u_arg[arg]);
-# endif
-#else
-# ifdef X32
-       if (current_personality == 0)
-               tprintf("%lld", tcp->ext_arg[arg]);
-       else
-# endif
+#if SIZEOF_KERNEL_LONG_T > 4
+# ifndef current_klongsize
+       if (current_klongsize < SIZEOF_KERNEL_LONG_T) {
+               tprintf("%" PRI_kld, (tcp->u_arg[arg + 1] << 32)
+                              | tcp->u_arg[arg]);
+       } else
+# endif /* !current_klongsize */
+       {
+               tprintf("%" PRI_kld, tcp->u_arg[arg]);
+       }
+#else /* SIZEOF_KERNEL_LONG_T == 4 */
        tprintf("%lld",
-               ((unsigned long long) (unsigned long) tcp->u_arg[arg + 1] << sizeof(long) * 8)
-               | (unsigned long long) (unsigned long) tcp->u_arg[arg]);
+                 ((long long) tcp->u_arg[arg + 1] << 32)
+               | ((long long) tcp->u_arg[arg]));
 #endif
 }
 
@@ -216,9 +206,13 @@ do_preadv(struct tcb *tcp, const int flags_arg)
                printfd(tcp, tcp->u_arg[0]);
                tprints(", ");
        } else {
-               tprint_iov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1], 1,
-                               tcp->u_rval);
-               tprintf(", %lu, ", tcp->u_arg[2]);
+               kernel_ulong_t len =
+                       truncate_kulong_to_current_wordsize(tcp->u_arg[2]);
+
+               tprint_iov_upto(tcp, len, tcp->u_arg[1],
+                               syserror(tcp) ? IOV_DECODE_ADDR :
+                               IOV_DECODE_STR, tcp->u_rval);
+               tprintf(", %" PRI_klu ", ", len);
                print_lld_from_low_high_val(tcp, 3);
                if (flags_arg >= 0) {
                        tprints(", ");
@@ -233,18 +227,16 @@ SYS_FUNC(preadv)
        return do_preadv(tcp, -1);
 }
 
-SYS_FUNC(preadv2)
-{
-       return do_preadv(tcp, 5);
-}
-
 static int
 do_pwritev(struct tcb *tcp, const int flags_arg)
 {
+       kernel_ulong_t len =
+               truncate_kulong_to_current_wordsize(tcp->u_arg[2]);
+
        printfd(tcp, tcp->u_arg[0]);
        tprints(", ");
-       tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
-       tprintf(", %lu, ", tcp->u_arg[2]);
+       tprint_iov(tcp, len, tcp->u_arg[1], IOV_DECODE_STR);
+       tprintf(", %" PRI_klu ", ", len);
        print_lld_from_low_high_val(tcp, 3);
        if (flags_arg >= 0) {
                tprints(", ");
@@ -259,9 +251,29 @@ SYS_FUNC(pwritev)
        return do_pwritev(tcp, -1);
 }
 
+/*
+ * x32 is the only architecture where preadv2 takes 5 arguments
+ * instead of 6, see preadv64v2 in kernel sources.
+ * Likewise, x32 is the only architecture where pwritev2 takes 5 arguments
+ * instead of 6, see pwritev64v2 in kernel sources.
+ */
+
+#if defined X86_64
+# define PREADV2_PWRITEV2_FLAGS_ARG_NO (current_personality == 2 ? 4 : 5)
+#elif defined X32
+# define PREADV2_PWRITEV2_FLAGS_ARG_NO (current_personality == 0 ? 4 : 5)
+#else
+# define PREADV2_PWRITEV2_FLAGS_ARG_NO 5
+#endif
+
+SYS_FUNC(preadv2)
+{
+       return do_preadv(tcp, PREADV2_PWRITEV2_FLAGS_ARG_NO);
+}
+
 SYS_FUNC(pwritev2)
 {
-       return do_pwritev(tcp, 5);
+       return do_pwritev(tcp, PREADV2_PWRITEV2_FLAGS_ARG_NO);
 }
 
 #include "xlat/splice_flags.h"
@@ -275,7 +287,7 @@ SYS_FUNC(tee)
        printfd(tcp, tcp->u_arg[1]);
        tprints(", ");
        /* size_t len */
-       tprintf("%lu, ", tcp->u_arg[2]);
+       tprintf("%" PRI_klu ", ", tcp->u_arg[2]);
        /* unsigned int flags */
        printflags(splice_flags, tcp->u_arg[3], "SPLICE_F_???");
 
@@ -297,7 +309,7 @@ SYS_FUNC(splice)
        printnum_int64(tcp, tcp->u_arg[3], "%" PRId64);
        tprints(", ");
        /* size_t len */
-       tprintf("%lu, ", tcp->u_arg[4]);
+       tprintf("%" PRI_klu ", ", tcp->u_arg[4]);
        /* unsigned int flags */
        printflags(splice_flags, tcp->u_arg[5], "SPLICE_F_???");
 
@@ -310,8 +322,8 @@ SYS_FUNC(vmsplice)
        printfd(tcp, tcp->u_arg[0]);
        tprints(", ");
        /* const struct iovec *iov, unsigned long nr_segs */
-       tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], 1);
-       tprintf(", %lu, ", tcp->u_arg[2]);
+       tprint_iov(tcp, tcp->u_arg[2], tcp->u_arg[1], IOV_DECODE_STR);
+       tprintf(", %" PRI_klu ", ", tcp->u_arg[2]);
        /* unsigned int flags */
        printflags(splice_flags, tcp->u_arg[3], "SPLICE_F_???");