diff options
author | Luck, Tony <tony.luck@intel.com> | 2019-07-30 21:39:57 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-25 10:53:00 +0200 |
commit | b88f8f192e2b7582d62c5176caf31cc6bf3355cc (patch) | |
tree | ece6008e8b94b0090e8469f18c119a6dfa106309 | |
parent | 81882762061b93890ca50d975cb90ee61ccab194 (diff) |
IB/core: Add mitigation for Spectre V1
[ Upstream commit 61f259821dd3306e49b7d42a3f90fb5a4ff3351b ]
Some processors may mispredict an array bounds check and
speculatively access memory that they should not. With
a user supplied array index we like to play things safe
by masking the value with the array size before it is
used as an index.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20190731043957.GA1600@agluck-desk2.amr.corp.intel.com
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | drivers/infiniband/core/user_mad.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c index 57f281f8d686..e9e75f40714c 100644 --- a/drivers/infiniband/core/user_mad.c +++ b/drivers/infiniband/core/user_mad.c @@ -49,6 +49,7 @@ #include <linux/sched.h> #include <linux/semaphore.h> #include <linux/slab.h> +#include <linux/nospec.h> #include <asm/uaccess.h> @@ -842,11 +843,14 @@ static int ib_umad_unreg_agent(struct ib_umad_file *file, u32 __user *arg) if (get_user(id, arg)) return -EFAULT; + if (id >= IB_UMAD_MAX_AGENTS) + return -EINVAL; mutex_lock(&file->port->file_mutex); mutex_lock(&file->mutex); - if (id >= IB_UMAD_MAX_AGENTS || !__get_agent(file, id)) { + id = array_index_nospec(id, IB_UMAD_MAX_AGENTS); + if (!__get_agent(file, id)) { ret = -EINVAL; goto out; } |