lightnvm: check overflow and correct mlc pairs
The specification currently limits the number of MLC pairs to 886. Make
sure that a device is unable to be instantiate if more is configured.
Also, previously the patch had the wrong math for copying MLC pairs, as
it only copied half of the actual entries.
Fixes: ca5927e7ab53 "lightnvm: introduce mlc lower page table mappings"
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 5cd3725..6bb15e4 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -146,9 +146,10 @@
};
};
+#define NVME_NVM_LP_MLC_PAIRS 886
struct nvme_nvm_lp_mlc {
__u16 num_pairs;
- __u8 pairs[886];
+ __u8 pairs[NVME_NVM_LP_MLC_PAIRS];
};
struct nvme_nvm_lp_tbl {
@@ -282,9 +283,14 @@
memcpy(dst->lptbl.id, src->lptbl.id, 8);
dst->lptbl.mlc.num_pairs =
le16_to_cpu(src->lptbl.mlc.num_pairs);
- /* 4 bits per pair */
+
+ if (dst->lptbl.mlc.num_pairs > NVME_NVM_LP_MLC_PAIRS) {
+ pr_err("nvm: number of MLC pairs not supported\n");
+ return -EINVAL;
+ }
+
memcpy(dst->lptbl.mlc.pairs, src->lptbl.mlc.pairs,
- dst->lptbl.mlc.num_pairs >> 1);
+ dst->lptbl.mlc.num_pairs);
}
}