This is a note to let you know that I've just added the patch titled
net: mvneta: Fix an out of bounds check
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-mvneta-fix-an-out-of-bounds-check.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1259e2a5297fa60af6d29c0449195c7109fc5c83
Author: Dan Carpenter <error27@xxxxxxxxx>
Date: Wed Dec 7 10:06:31 2022 +0300
net: mvneta: Fix an out of bounds check
[ Upstream commit cdd97383e19d4afe29adc3376025a15ae3bab3a3 ]
In an earlier commit, I added a bounds check to prevent an out of bounds
read and a WARN(). On further discussion and consideration that check
was probably too aggressive. Instead of returning -EINVAL, a better fix
would be to just prevent the out of bounds read but continue the process.
Background: The value of "pp->rxq_def" is a number between 0-7 by default,
or even higher depending on the value of "rxq_number", which is a module
parameter. If the value is more than the number of available CPUs then
it will trigger the WARN() in cpu_max_bits_warn().
Fixes: e8b4fc13900b ("net: mvneta: Prevent out of bounds read in mvneta_config_rss()")
Signed-off-by: Dan Carpenter <error27@xxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Link: https://lore.kernel.org/r/Y5A7d1E5ccwHTYPf@kadam
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 86eb258ed811..b2d42d276efd 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -3278,7 +3278,7 @@ static void mvneta_percpu_elect(struct mvneta_port *pp)
/* Use the cpu associated to the rxq when it is online, in all
* the other cases, use the cpu 0 which can't be offline.
*/
- if (cpu_online(pp->rxq_def))
+ if (pp->rxq_def < nr_cpu_ids && cpu_online(pp->rxq_def))
elected_cpu = pp->rxq_def;
max_cpu = num_present_cpus();
@@ -3761,9 +3761,6 @@ static int mvneta_config_rss(struct mvneta_port *pp)
napi_disable(&pcpu_port->napi);
}
- if (pp->indir[0] >= nr_cpu_ids)
- return -EINVAL;
-
pp->rxq_def = pp->indir[0];
/* Update unicast mapping */
