[PULL for-6.0 v2 09/10] hw/block/nvme: fix assert crash in nvme_subsys_ns

[Klaus Jensen <its@irrelevant.dk>]

From: Klaus Jensen <k.jensen@samsung.com>

nvme_subsys_ns() is used in contexts where the namespace identifier is
taken from an untrusted source. Commit 3921756dee6d ("hw/block/nvme:
assert namespaces array indices") tried to guard against this by
introducing an assert on the namespace identifier.

This is wrong since it is perfectly valid to call the function with an
invalid namespace identifier and like nvme_ns(), nvme_subsys_ns() should
simply return NULL.

Fixes: 3921756dee6d ("hw/block/nvme: assert namespaces array indices")
Fixes: 94d8d6d16781 ("hw/block/nvme: support allocated namespace type")
Cc: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
---
 hw/block/nvme-subsys.h | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/hw/block/nvme-subsys.h b/hw/block/nvme-subsys.h
index 24132edd005c..1cbcad9be23e 100644
--- a/hw/block/nvme-subsys.h
+++ b/hw/block/nvme-subsys.h
@@ -49,12 +49,10 @@ static inline NvmeCtrl *nvme_subsys_ctrl(NvmeSubsystem *subsys,
 static inline NvmeNamespace *nvme_subsys_ns(NvmeSubsystem *subsys,
         uint32_t nsid)
 {
-    if (!subsys) {
+    if (!subsys || !nsid || nsid > NVME_MAX_NAMESPACES) {
         return NULL;
     }
 
-    assert(nsid && nsid <= NVME_MAX_NAMESPACES);
-
     return subsys->namespaces[nsid];
 }
 
-- 
2.31.1