This is a note to let you know that I've just added the patch titled 6lowpan: iphc: Fix an off-by-one check of array index to the 5.14-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: 6lowpan-iphc-fix-an-off-by-one-check-of-array-index.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit d1b2e6dcaa744c3abe51777e212967147218071f Author: Colin Ian King <colin.king@xxxxxxxxxxxxx> Date: Mon Jul 12 13:14:40 2021 +0100 6lowpan: iphc: Fix an off-by-one check of array index [ Upstream commit 9af417610b6142e826fd1ee8ba7ff3e9a2133a5a ] The bounds check of id is off-by-one and the comparison should be >= rather >. Currently the WARN_ON_ONCE check does not stop the out of range indexing of &ldev->ctx.table[id] so also add a return path if the bounds are out of range. Addresses-Coverity: ("Illegal address computation"). Fixes: 5609c185f24d ("6lowpan: iphc: add support for stateful compression") Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/6lowpan/debugfs.c b/net/6lowpan/debugfs.c index 1c140af06d52..600b9563bfc5 100644 --- a/net/6lowpan/debugfs.c +++ b/net/6lowpan/debugfs.c @@ -170,7 +170,8 @@ static void lowpan_dev_debugfs_ctx_init(struct net_device *dev, struct dentry *root; char buf[32]; - WARN_ON_ONCE(id > LOWPAN_IPHC_CTX_TABLE_SIZE); + if (WARN_ON_ONCE(id >= LOWPAN_IPHC_CTX_TABLE_SIZE)) + return; sprintf(buf, "%d", id);