From: Zorro Lang <zlang@redhat.com>
To: linux-xfs@vger.kernel.org
Subject: [PATCH v2] xfsprogs: fix wrong variable type in write_once function
Date: Sat, 11 Nov 2017 21:57:59 +0800 [thread overview]
Message-ID: <20171111135759.7431-1-zlang@redhat.com> (raw)
The 'Coverity Scan' found a problem in new write_once() function:
272 size_t bytes;
273 bytes = do_pwrite(file->fd, offset, count, count, pwritev2_flags);
>>> CID 1420710: Control flow issues (NO_EFFECT)
>>> This less-than-zero comparison of an unsigned value is never true. "bytes < 0UL".
274 if (bytes < 0)
275 return -1;
That's unreasonable. do_pwrite return 'ssize_t' type value, which can
be less than zero, but we use a 'size_t' to get the return value. So
change the size_t to ssize_t for it can store the return value
correctly.
By the chance, correct all 'ssize_t' type problems in pwrite related
functions.
Signed-off-by: Zorro Lang <zlang@redhat.com>
---
V2 changed more than V1, as below:
1) The return value type of do_pwritev and do_pwrite, from 'int' to 'ssize_t'
2) The arguments type of do_pwritev and do_pwrite, from 'ssize_t' to 'size_t'
Thanks,
Zorro
io/pwrite.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/io/pwrite.c b/io/pwrite.c
index 26f79579..3df976a8 100644
--- a/io/pwrite.c
+++ b/io/pwrite.c
@@ -61,12 +61,12 @@ pwrite_help(void)
}
#ifdef HAVE_PWRITEV
-static int
+static ssize_t
do_pwritev(
int fd,
off64_t offset,
- ssize_t count,
- ssize_t buffer_size,
+ size_t count,
+ size_t buffer_size,
int pwritev2_flags)
{
int vecs = 0;
@@ -105,12 +105,12 @@ do_pwritev(
#define do_pwritev(fd, offset, count, buffer_size) (0)
#endif
-static int
+static ssize_t
do_pwrite(
int fd,
off64_t offset,
- ssize_t count,
- ssize_t buffer_size,
+ size_t count,
+ size_t buffer_size,
int pwritev2_flags)
{
if (!vectors)
@@ -269,7 +269,7 @@ write_once(
long long *total,
int pwritev2_flags)
{
- size_t bytes;
+ ssize_t bytes;
bytes = do_pwrite(file->fd, offset, count, count, pwritev2_flags);
if (bytes < 0)
return -1;
--
2.13.6
next reply other threads:[~2017-11-11 13:58 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-11 13:57 Zorro Lang [this message]
2017-11-11 15:46 ` [PATCH v2] xfsprogs: fix wrong variable type in write_once function Eric Sandeen
2017-11-11 16:22 ` Zorro Lang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20171111135759.7431-1-zlang@redhat.com \
--to=zlang@redhat.com \
--cc=linux-xfs@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.