linux-kernel - [PATCH -next] pstore: make reason_str robust for future re-arrangements of the enum values

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <5C4C569E8A4B9B42A84A977CF070A35B2E4B8EFF90@USINDEVS01.corp.hds.com>
Date:	Mon, 26 Mar 2012 12:06:44 -0400
From:	Seiji Aguchi <seiji.aguchi@....com>
To:	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	"Adrian Hunter (adrian.hunter@...el.com)" <adrian.hunter@...el.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"Luck, Tony (tony.luck@...el.com)" <tony.luck@...el.com>,
	"dzickus@...hat.com" <dzickus@...hat.com>,
	"Chen Gong (gong.chen@...ux.intel.com)" <gong.chen@...ux.intel.com>,
	"Matthew Garrett (mjg@...hat.com)" <mjg@...hat.com>
CC:	"dle-develop@...ts.sourceforge.net" 
	<dle-develop@...ts.sourceforge.net>,
	Satoru Moriya <satoru.moriya@....com>
Subject: [PATCH -next] pstore: make reason_str robust for future
 re-arrangements of the enum values

Hi,

Recently, there has been some changes in kmsg_dump() below and they have been applied to linus-tree. 
 (1) kmsg_dump(KMSG_DUMP_KEXEC) was removed.
     http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=a3dd3323058d281abd584b15ad4c5b65064d7a61

 (2) A order of "enum kmsg_dump_reason" was modified.
     http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=c22ab332902333f83766017478c1ef6607ace681

 This patch replaces get_reason_str() with reason_str array in accordance with akpm's comment below.
 https://lkml.org/lkml/2012/3/24/18

 It will not be broken by future re-arrangements of the enum values.

 Signed-off-by: Seiji Aguchi <seiji.aguchi@....com>

---
 fs/pstore/platform.c |   32 ++++++++++++--------------------
 1 files changed, 12 insertions(+), 20 deletions(-)

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 82c585f..e8a14cd 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -68,25 +68,14 @@ void pstore_set_kmsg_bytes(int bytes)
 /* Tag each group of saved records with a sequence number */
 static int	oopscount;
 
-static const char *get_reason_str(enum kmsg_dump_reason reason)
-{
-	switch (reason) {
-	case KMSG_DUMP_PANIC:
-		return "Panic";
-	case KMSG_DUMP_OOPS:
-		return "Oops";
-	case KMSG_DUMP_EMERG:
-		return "Emergency";
-	case KMSG_DUMP_RESTART:
-		return "Restart";
-	case KMSG_DUMP_HALT:
-		return "Halt";
-	case KMSG_DUMP_POWEROFF:
-		return "Poweroff";
-	default:
-		return "Unknown";
-	}
-}
+static const char * const reason_str[] = {
+	[KMSG_DUMP_PANIC] = "Panic",
+	[KMSG_DUMP_OOPS] = "Oops",
+	[KMSG_DUMP_EMERG] = "Emergency",
+	[KMSG_DUMP_RESTART] = "Restart",
+	[KMSG_DUMP_HALT] = "Halt",
+	[KMSG_DUMP_POWEROFF] = "Poweroff",
+};
 
 /*
  * callback from kmsg_dump. (s2,l2) has the most recently
@@ -109,7 +98,10 @@ static void pstore_dump(struct kmsg_dumper *dumper,
 	unsigned long	flags = 0;
 	int		is_locked = 0;
 
-	why = get_reason_str(reason);
+	if (reason < ARRAY_SIZE(reason_str))
+		why = reason_str[reason];
+	else
+		why = "Unknown";
 
 	if (in_nmi()) {
 		is_locked = spin_trylock(&psinfo->buf_lock);
-- 1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/