netdev - [PATCH] bonding: cleanup bond

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>] [thread-next>] [day] [month] [year] [list]

Date:	Fri,  9 Jan 2015 13:31:08 -0500
From:	Jonathan Toppins <jtoppins@...ulusnetworks.com>
To:	netdev@...r.kernel.org
Cc:	shm@...ulusnetworks.com,
	Andy Gospodarek <gospo@...ulusnetworks.com>,
	Nikolay Aleksandrov <nikolay@...hat.com>
Subject: [PATCH] bonding: cleanup bond_opts array

Remove the empty array element initializer and size the array with
BOND_OPT_LAST so the compiler will complain if more elements are in
there than should be.

An interesting unwanted side effect of this initializer is that if one
inserts new options into the middle of the array then this initializer
will zero out the option that equals BOND_OPT_TLB_DYNAMIC_LB+1.

Example:
Extend the OPTS enum:
enum {
   ...
   BOND_OPT_TLB_DYNAMIC_LB,
   BOND_OPT_LACP_NEW1,
   BOND_OPT_LAST
};

Now insert into bond_opts array:
static const struct bond_option bond_opts[] = {
      ...
      [BOND_OPT_LACP_RATE] = { .... unchanged stuff .... },
      [BOND_OPT_LACP_NEW1] = { ... new stuff ... },
      ...
      [BOND_OPT_TLB_DYNAMIC_LB] = { .... unchanged stuff ....},
      { } // MARK A
};

Since BOND_OPT_LACP_NEW1 = BOND_OPT_TLB_DYNAMIC_LB+1, the last
initializer (MARK A) will overwrite the contents of BOND_OPT_LACP_NEW1
and can be easily viewed with the crash utility.

Signed-off-by: Jonathan Toppins <jtoppins@...ulusnetworks.com>
Cc: Andy Gospodarek <gospo@...ulusnetworks.com>
Cc: Nikolay Aleksandrov <nikolay@...hat.com>
---
 drivers/net/bonding/bond_options.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index 1a61cc9..9bd538d4 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -186,7 +186,7 @@ static const struct bond_opt_value bond_tlb_dynamic_lb_tbl[] = {
 	{ NULL,  -1, 0}
 };
 
-static const struct bond_option bond_opts[] = {
+static const struct bond_option bond_opts[BOND_OPT_LAST] = {
 	[BOND_OPT_MODE] = {
 		.id = BOND_OPT_MODE,
 		.name = "mode",
@@ -379,8 +379,7 @@ static const struct bond_option bond_opts[] = {
 		.values = bond_tlb_dynamic_lb_tbl,
 		.flags = BOND_OPTFLAG_IFDOWN,
 		.set = bond_option_tlb_dynamic_lb_set,
-	},
-	{ }
+	}
 };
 
 /* Searches for an option by name */
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html