2.6.32-longterm review patch. If anyone has any objections, please let me know.
------------------ From: Nikolay Aleksandrov <[email protected]> [ Upstream commit b869ccfab1e324507fa3596e3e1308444fb68227 ] This patch fixes two race conditions between bond_store_updelay/downdelay and bond_store_miimon which could lead to division by zero as miimon can be set to 0 while either updelay/downdelay are being set and thus miss the zero check in the beginning, the zero div happens because updelay/downdelay are stored as new_value / bond->params.miimon. Use rtnl to synchronize with miimon setting. CC: Jay Vosburgh <[email protected]> CC: Andy Gospodarek <[email protected]> CC: Veaceslav Falico <[email protected]> Signed-off-by: Nikolay Aleksandrov <[email protected]> Acked-by: Veaceslav Falico <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Willy Tarreau <[email protected]> --- drivers/net/bonding/bond_sysfs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index 8762a27..3666a9a 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -755,6 +755,8 @@ static ssize_t bonding_store_downdelay(struct device *d, int new_value, ret = count; struct bonding *bond = to_bond(d); + if (!rtnl_trylock()) + return restart_syscall(); if (!(bond->params.miimon)) { pr_err(DRV_NAME ": %s: Unable to set down delay as MII monitoring is disabled\n", @@ -795,6 +797,7 @@ static ssize_t bonding_store_downdelay(struct device *d, } out: + rtnl_unlock(); return ret; } static DEVICE_ATTR(downdelay, S_IRUGO | S_IWUSR, @@ -817,6 +820,8 @@ static ssize_t bonding_store_updelay(struct device *d, int new_value, ret = count; struct bonding *bond = to_bond(d); + if (!rtnl_trylock()) + return restart_syscall(); if (!(bond->params.miimon)) { pr_err(DRV_NAME ": %s: Unable to set up delay as MII monitoring is disabled\n", @@ -856,6 +861,7 @@ static ssize_t bonding_store_updelay(struct device *d, } out: + rtnl_unlock(); return ret; } static DEVICE_ATTR(updelay, S_IRUGO | S_IWUSR, -- 1.7.12.2.21.g234cd45.dirty -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
