preadv2/pwritev2: Handle offset == -1 [BZ #22753]

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

(cherry picked from commit d4b4a00a46)
This commit is contained in:
Florian Weimer 2018-02-02 10:46:26 +01:00 committed by Adhemerval Zanella
parent 9533f19aa5
commit 3b3775697a
14 changed files with 105 additions and 15 deletions

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@ -1,3 +1,20 @@
2018-09-28 Florian Weimer <fweimer@redhat.com>
[BZ #22753]
* sysdeps/posix/preadv2.c (preadv2): Handle offset == -1.
* sysdeps/posix/preadv64v2.c (preadv64v2): Likewise.
* sysdeps/posix/pwritev2.c (pwritev2): Likewise.
* sysdeps/posix/pwritev64v2.c (pwritev64v2): Likweise.
* sysdeps/unix/sysv/linux/preadv2.c (preadv2): Likewise.
* sysdeps/unix/sysv/linux/preadv64v2.c (preadv64v2): Likewise.
* sysdeps/unix/sysv/linux/pwritev2.c (pwritev2): Likewise.
* sysdeps/unix/sysv/linux/pwritev64v2.c (pwritev64v2): Likweise.
* manual/llio.texi (Scatter-Gather): Mention offset -1.
* misc/tst-preadvwritev-common.c (do_test_without_offset): New.
* misc/tst-preadvwritev2.c (do_test): Call it.
* misc/tst-preadvwritev64v2.c (do_test): Likewise.
* NEWS: Add bug fixed.
2018-09-06 Stefan Liebler <stli@linux.ibm.com>
* sysdeps/unix/sysv/linux/spawni.c (maybe_script_execute):

1
NEWS
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@ -53,6 +53,7 @@ The following bugs are resolved with this release:
[22644] memmove-sse2-unaligned on 32bit x86 produces garbage when crossing
2GB threshold
[22735] Misleading typo in time.h source comment regarding CLOCKS_PER_SECOND
[22753] libc: preadv2/pwritev2 fallback code should handle offset=-1
[22786] Stack buffer overflow in realpath() if input size is close
to SSIZE_MAX
[22797] Linux: use reserved name __key in pkey_get

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@ -1251,9 +1251,13 @@ When the source file is compiled using @code{_FILE_OFFSET_BITS == 64} on a
@c This is a syscall for Linux v4.6. The sysdeps/posix fallback emulation
@c is also MT-Safe since it calls preadv.
This function is similar to the @code{preadv} function, with the difference
it adds an extra @var{flags} parameter of type @code{int}. The supported
@var{flags} are dependent of the underlying system. For Linux it supports:
This function is similar to the @code{preadv} function, with the
difference it adds an extra @var{flags} parameter of type @code{int}.
Additionally, if @var{offset} is @math{-1}, the current file position
is used and updated (like the @code{readv} function).
The supported @var{flags} are dependent of the underlying system. For
Linux it supports:
@vtable @code
@item RWF_HIPRI
@ -1323,10 +1327,13 @@ When the source file is compiled using @code{_FILE_OFFSET_BITS == 64} on a
@c This is a syscall for Linux v4.6. The sysdeps/posix fallback emulation
@c is also MT-Safe since it calls pwritev.
This function is similar to the @code{pwritev} function, with the difference
it adds an extra @var{flags} parameter of type @code{int}. The supported
@var{flags} are dependent of the underlying system and for Linux it supports
the same ones as for @code{preadv2}.
This function is similar to the @code{pwritev} function, with the
difference it adds an extra @var{flags} parameter of type @code{int}.
Additionally, if @var{offset} is @math{-1}, the current file position
should is used and updated (like the @code{writev} function).
The supported @var{flags} are dependent of the underlying system. For
Linux, the supported flags are the same as those for @code{preadv2}.
When the source file is compiled with @code{_FILE_OFFSET_BITS == 64} the
@code{pwritev2} function is in fact @code{pwritev64v2} and the type

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@ -16,6 +16,7 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <array_length.h>
#include <stdio.h>
#include <stdint.h>
#include <errno.h>
@ -25,6 +26,7 @@
#include <support/check.h>
#include <support/temp_file.h>
#include <support/xunistd.h>
static char *temp_filename;
static int temp_fd;
@ -50,6 +52,42 @@ do_prepare (int argc, char **argv)
pwritev (__fd, __iov, __iovcnt, __offset)
#endif
static __attribute__ ((unused)) void
do_test_without_offset (void)
{
xftruncate (temp_fd, 0);
xwrite (temp_fd, "123", 3);
xlseek (temp_fd, 2, SEEK_SET);
{
struct iovec iov[] =
{
{ (void *) "abc", 3 },
{ (void *) "xyzt", 4 },
};
TEST_COMPARE (PWRITEV (temp_fd, iov, array_length (iov), -1), 7);
}
TEST_COMPARE (xlseek (temp_fd, 0, SEEK_CUR), 9);
xlseek (temp_fd, 1, SEEK_SET);
char buf1[3];
char buf2[2];
{
struct iovec iov[] =
{
{ buf1, sizeof (buf1) },
{ buf2, sizeof (buf2) },
};
TEST_COMPARE (PREADV (temp_fd, iov, array_length (iov), -1),
sizeof (buf1) + sizeof (buf2));
TEST_COMPARE (memcmp ("2ab", buf1, sizeof (buf1)), 0);
TEST_COMPARE (memcmp ("cx", buf2, sizeof (buf2)), 0);
TEST_COMPARE (xlseek (temp_fd, 0, SEEK_CUR), 6);
}
xftruncate (temp_fd, 0);
}
static int
do_test_with_offset (off_t offset)
{

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@ -29,6 +29,7 @@ static int
do_test (void)
{
do_test_with_invalid_flags ();
do_test_without_offset ();
return do_test_with_offset (0);
}

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@ -31,6 +31,7 @@ static int
do_test (void)
{
do_test_with_invalid_flags ();
do_test_without_offset ();
return do_test_with_offset (0);
}

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@ -33,7 +33,10 @@ preadv2 (int fd, const struct iovec *vector, int count, off_t offset,
return -1;
}
return preadv (fd, vector, count, offset);
if (offset == -1)
return __readv (fd, vector, count);
else
return preadv (fd, vector, count, offset);
}
#endif

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@ -30,7 +30,10 @@ preadv64v2 (int fd, const struct iovec *vector, int count, off64_t offset,
return -1;
}
return preadv64 (fd, vector, count, offset);
if (offset == -1)
return __readv (fd, vector, count);
else
return preadv64 (fd, vector, count, offset);
}
#ifdef __OFF_T_MATCHES_OFF64_T

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@ -33,7 +33,10 @@ pwritev2 (int fd, const struct iovec *vector, int count, off_t offset,
return -1;
}
return pwritev (fd, vector, count, offset);
if (offset == -1)
return __writev (fd, vector, count);
else
return pwritev (fd, vector, count, offset);
}
#endif

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@ -31,7 +31,10 @@ pwritev64v2 (int fd, const struct iovec *vector, int count, off64_t offset,
return -1;
}
return pwritev64 (fd, vector, count, offset);
if (offset == -1)
return __writev (fd, vector, count);
else
return pwritev64 (fd, vector, count, offset);
}
#ifdef __OFF_T_MATCHES_OFF64_T

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@ -49,7 +49,10 @@ preadv2 (int fd, const struct iovec *vector, int count, off_t offset,
__set_errno (ENOTSUP);
return -1;
}
return preadv (fd, vector, count, offset);
if (offset == -1)
return __readv (fd, vector, count);
else
return preadv (fd, vector, count, offset);
}
#endif

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@ -47,7 +47,11 @@ preadv64v2 (int fd, const struct iovec *vector, int count, off64_t offset,
__set_errno (ENOTSUP);
return -1;
}
return preadv64 (fd, vector, count, offset);
if (offset == -1)
return __readv (fd, vector, count);
else
return preadv64 (fd, vector, count, offset);
}
#ifdef __OFF_T_MATCHES_OFF64_T

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@ -45,7 +45,10 @@ pwritev2 (int fd, const struct iovec *vector, int count, off_t offset,
__set_errno (ENOTSUP);
return -1;
}
return pwritev (fd, vector, count, offset);
if (offset == -1)
return __writev (fd, vector, count);
else
return pwritev (fd, vector, count, offset);
}
#endif

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@ -47,7 +47,10 @@ pwritev64v2 (int fd, const struct iovec *vector, int count, off64_t offset,
__set_errno (ENOTSUP);
return -1;
}
return pwritev64 (fd, vector, count, offset);
if (offset == -1)
return __writev (fd, vector, count);
else
return pwritev64 (fd, vector, count, offset);
}
#ifdef __OFF_T_MATCHES_OFF64_T