[PATCH] device-tree: fix infinite loop issue in 'assign_shared_memory()'

[Dmytro Prokopchuk1]

Resolve infinite loop issue in the 'fail:' cleanup path of the function
'assign_shared_memory()'. The issue was caused by an 'unsigned long' type
for the loop counter 'i', which could underflow and wrap around, violating
termination conditions.
Change 'i' to a signed data type ('long') to ensure safe termination of
the 'while (--i >= 0)' loop.

This change adheres to MISRA Rule R14.3: "Controlling expressions shall
not be invariant."

Signed-off-by: Dmytro Prokopchuk <dmytro_prokopch...@epam.com>
---
 xen/common/device-tree/static-shmem.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/common/device-tree/static-shmem.c 
b/xen/common/device-tree/static-shmem.c
index 8023c0a484..b4c772466c 100644
--- a/xen/common/device-tree/static-shmem.c
+++ b/xen/common/device-tree/static-shmem.c
@@ -134,7 +134,8 @@ static int __init assign_shared_memory(struct domain *d, 
paddr_t gbase,
 {
     mfn_t smfn;
     int ret = 0;
-    unsigned long nr_pages, nr_borrowers, i;
+    unsigned long nr_pages, nr_borrowers;
+    long i;
     struct page_info *page;
     paddr_t pbase, psize;
 
-- 
2.43.0