[PATCH] asm-generic: allow unaligned buffers in reads/writes{w,l,q}
From: Julian Vetter
Date: Mon Feb 03 2025 - 08:03:56 EST
Access buffers in reads/writes{w,l,q} via get_unaligned and
put_unaligned, to protect from potential unaligned traps.
Signed-off-by: Julian Vetter <julian@xxxxxxxxxxxxxxxx>
---
include/asm-generic/io.h | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index a5cbbf3e26ec..920fecd512fc 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -12,6 +12,7 @@
#include <linux/sizes.h>
#include <linux/types.h>
#include <linux/instruction_pointer.h>
+#include <linux/unaligned.h>
#ifdef CONFIG_GENERIC_IOMAP
#include <asm-generic/iomap.h>
@@ -422,7 +423,8 @@ static inline void readsw(const volatile void __iomem *addr, void *buffer,
do {
u16 x = __raw_readw(addr);
- *buf++ = x;
+ put_unaligned(x, buf);
+ buf++;
} while (--count);
}
}
@@ -438,7 +440,8 @@ static inline void readsl(const volatile void __iomem *addr, void *buffer,
do {
u32 x = __raw_readl(addr);
- *buf++ = x;
+ put_unaligned(x, buf);
+ buf++;
} while (--count);
}
}
@@ -455,7 +458,8 @@ static inline void readsq(const volatile void __iomem *addr, void *buffer,
do {
u64 x = __raw_readq(addr);
- *buf++ = x;
+ put_unaligned(x, buf);
+ buf++;
} while (--count);
}
}
@@ -486,7 +490,9 @@ static inline void writesw(volatile void __iomem *addr, const void *buffer,
const u16 *buf = buffer;
do {
- __raw_writew(*buf++, addr);
+ u16 val = get_unaligned(buf);
+ __raw_writew(val, addr);
+ buf++;
} while (--count);
}
}
@@ -501,7 +507,9 @@ static inline void writesl(volatile void __iomem *addr, const void *buffer,
const u32 *buf = buffer;
do {
- __raw_writel(*buf++, addr);
+ u32 val = get_unaligned(buf);
+ __raw_writel(val, addr);
+ buf++;
} while (--count);
}
}
@@ -517,7 +525,9 @@ static inline void writesq(volatile void __iomem *addr, const void *buffer,
const u64 *buf = buffer;
do {
- __raw_writeq(*buf++, addr);
+ u64 val = get_unaligned(buf);
+ __raw_writeq(val, addr);
+ buf++;
} while (--count);
}
}
--
2.34.1