This patch fixes the smatch warning, "nvmet_ns_ana_grpid_store() warn:
potential spectre issue 'nvmet_ana_group_enabled' [w] (local cap)"
Prevent the contents of kernel memory from being leaked to user space
via speculative execution by using array_index_nospec.
Signed-off-by: Nitesh Shetty <[email protected]>
---
drivers/nvme/target/configfs.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index e307a044b1a1..d937fe05129e 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -18,6 +18,7 @@
#include <linux/nvme-keyring.h>
#include <crypto/hash.h>
#include <crypto/kpp.h>
+#include <linux/nospec.h>
#include "nvmet.h"
@@ -621,6 +622,7 @@ static ssize_t nvmet_ns_ana_grpid_store(struct config_item *item,
down_write(&nvmet_ana_sem);
oldgrpid = ns->anagrpid;
+ newgrpid = array_index_nospec(newgrpid, NVMET_MAX_ANAGRPS);
nvmet_ana_group_enabled[newgrpid]++;
ns->anagrpid = newgrpid;
nvmet_ana_group_enabled[oldgrpid]--;
@@ -1812,6 +1814,7 @@ static struct config_group *nvmet_ana_groups_make_group(
grp->grpid = grpid;
down_write(&nvmet_ana_sem);
+ grpid = array_index_nospec(grpid, NVMET_MAX_ANAGRPS);
nvmet_ana_group_enabled[grpid]++;
up_write(&nvmet_ana_sem);
--
2.35.1.500.gb896f729e2
Reviewed-by: Sagi Grimberg <[email protected]>
On Tue, Nov 28, 2023 at 05:59:57PM +0530, Nitesh Shetty wrote:
> This patch fixes the smatch warning, "nvmet_ns_ana_grpid_store() warn:
> potential spectre issue 'nvmet_ana_group_enabled' [w] (local cap)"
> Prevent the contents of kernel memory from being leaked to user space
> via speculative execution by using array_index_nospec.
>
> Signed-off-by: Nitesh Shetty <[email protected]>
> ---
When it comes to adding array_index_nospec(), then I don't know enough
about it to comment.
regards,
dan carpenter
Looks good:
Reviewed-by: Christoph Hellwig <[email protected]>