Kexec Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Petr Tesarik <ptesarik@suse.cz>
To: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: "kexec@lists.infradead.org" <kexec@lists.infradead.org>
Subject: [PATCH] dump_log_entry: replace magic constant with a variable
Date: Fri, 29 Aug 2014 10:36:20 +0200	[thread overview]
Message-ID: <20140829103620.15aee556@hananiah.suse.cz> (raw)

If the buffer space requirements are changed, the magic constant is
hard to spot, and the failure is easily overlooked, because it may
fail only under special conditions.

Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
---
 makedumpfile.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/makedumpfile.c b/makedumpfile.c
index b4b6eca..37dea37 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -3949,7 +3949,7 @@ static int
 dump_log_entry(char *logptr, int fp)
 {
 	char *msg, *p, *bufp;
-	unsigned int i, text_len;
+	unsigned int i, text_len, buf_need;
 	unsigned long long ts_nsec;
 	char buf[BUFSIZE];
 	ulonglong nanos;
@@ -3966,9 +3966,11 @@ dump_log_entry(char *logptr, int fp)
 	bufp = buf;
 	bufp += sprintf(buf, "[%5lld.%06ld] ", nanos, rem/1000);
 
+	/* How much buffer space is needed in the worst case */
+	buf_need = sizeof("\\xXX\n");
+
 	for (i = 0, p = msg; i < text_len; i++, p++) {
-		/* 6bytes = "\\x%02x" + '\n' + '\0' */
-		if (bufp - buf >= sizeof(buf) - 6) {
+		if (bufp - buf >= sizeof(buf) - buf_need) {
 			if (write(info->fd_dumpfile, buf, bufp - buf) < 0)
 				return FALSE;
 			bufp = buf;
-- 

_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec

             reply	other threads:[~2014-08-29  8:36 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-29  8:36 Petr Tesarik [this message]
2014-09-01  6:37 ` [PATCH] dump_log_entry: replace magic constant with a variable Atsushi Kumagai
2014-09-01  7:17   ` Petr Tesarik

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=20140829103620.15aee556@hananiah.suse.cz \
    --to=ptesarik@suse.cz \
    --cc=kexec@lists.infradead.org \
    --cc=kumagai-atsushi@mxc.nes.nec.co.jp \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox