[tip: x86/urgent] x86/ioremap: Use is_ioremap_addr() in iounmap()

["tip-bot2 for Max Ramanouski" <tip-bot2@linutronix.de>]

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     7b02ad32d83c16abd4961d79f3154b734d1d5d9c
Gitweb:        https://git.kernel.org/tip/7b02ad32d83c16abd4961d79f3154b734d1d5d9c
Author:        Max Ramanouski <max8rr8@gmail.com>
AuthorDate:    Thu, 15 Aug 2024 23:56:07 +03:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Fri, 16 Aug 2024 11:33:33 +02:00

x86/ioremap: Use is_ioremap_addr() in iounmap()

Restrict iounmap() to memory allocated in the ioremap region, by using
is_ioremap_addr(). Similarly to the generic iounmap() implementation.

Additionally, add a warning in case there is an attempt to iounmap()
invalid memory, instead of silently exiting, thus helping to avoid
incorrect usage of iounmap().

Signed-off-by: Max Ramanouski <max8rr8@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://lore.kernel.org/all/20240815205606.16051-2-max8rr8@gmail.com
---
 arch/x86/mm/ioremap.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index aa7d279..70b02fc 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -11,6 +11,7 @@
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
+#include <linux/ioremap.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include <linux/mmiotrace.h>
@@ -457,7 +458,7 @@ void iounmap(volatile void __iomem *addr)
 {
 	struct vm_struct *p, *o;
 
-	if ((void __force *)addr <= high_memory)
+	if (WARN_ON_ONCE(!is_ioremap_addr((void __force *)addr)))
 		return;
 
 	/*