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authorAlexander Potapenko <glider@google.com>2022-09-15 18:03:53 +0300
committerAndrew Morton <akpm@linux-foundation.org>2022-10-04 00:03:21 +0300
commita28a4d4723c11fe5fd3e725f5eb1b3472e80fe12 (patch)
tree0752c5c93e69a20045240757c365ce646aa11523 /lib/iomap.c
parent75cf0290271bf6dae9dee982aef15242dadf97e4 (diff)
downloadlinux-a28a4d4723c11fe5fd3e725f5eb1b3472e80fe12.tar.xz
kmsan: add iomap support
Functions from lib/iomap.c interact with hardware, so KMSAN must ensure that: - every read function returns an initialized value - every write function checks values before sending them to hardware. Link: https://lkml.kernel.org/r/20220915150417.722975-20-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'lib/iomap.c')
-rw-r--r--lib/iomap.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/lib/iomap.c b/lib/iomap.c
index fbaa3e8f19d6..4f8b31baa575 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -6,6 +6,7 @@
*/
#include <linux/pci.h>
#include <linux/io.h>
+#include <linux/kmsan-checks.h>
#include <linux/export.h>
@@ -70,26 +71,35 @@ static void bad_io_access(unsigned long port, const char *access)
#define mmio_read64be(addr) swab64(readq(addr))
#endif
+/*
+ * Here and below, we apply __no_kmsan_checks to functions reading data from
+ * hardware, to ensure that KMSAN marks their return values as initialized.
+ */
+__no_kmsan_checks
unsigned int ioread8(const void __iomem *addr)
{
IO_COND(addr, return inb(port), return readb(addr));
return 0xff;
}
+__no_kmsan_checks
unsigned int ioread16(const void __iomem *addr)
{
IO_COND(addr, return inw(port), return readw(addr));
return 0xffff;
}
+__no_kmsan_checks
unsigned int ioread16be(const void __iomem *addr)
{
IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
return 0xffff;
}
+__no_kmsan_checks
unsigned int ioread32(const void __iomem *addr)
{
IO_COND(addr, return inl(port), return readl(addr));
return 0xffffffff;
}
+__no_kmsan_checks
unsigned int ioread32be(const void __iomem *addr)
{
IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
@@ -142,18 +152,21 @@ static u64 pio_read64be_hi_lo(unsigned long port)
return lo | (hi << 32);
}
+__no_kmsan_checks
u64 ioread64_lo_hi(const void __iomem *addr)
{
IO_COND(addr, return pio_read64_lo_hi(port), return readq(addr));
return 0xffffffffffffffffULL;
}
+__no_kmsan_checks
u64 ioread64_hi_lo(const void __iomem *addr)
{
IO_COND(addr, return pio_read64_hi_lo(port), return readq(addr));
return 0xffffffffffffffffULL;
}
+__no_kmsan_checks
u64 ioread64be_lo_hi(const void __iomem *addr)
{
IO_COND(addr, return pio_read64be_lo_hi(port),
@@ -161,6 +174,7 @@ u64 ioread64be_lo_hi(const void __iomem *addr)
return 0xffffffffffffffffULL;
}
+__no_kmsan_checks
u64 ioread64be_hi_lo(const void __iomem *addr)
{
IO_COND(addr, return pio_read64be_hi_lo(port),
@@ -188,22 +202,32 @@ EXPORT_SYMBOL(ioread64be_hi_lo);
void iowrite8(u8 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, outb(val,port), writeb(val, addr));
}
void iowrite16(u16 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, outw(val,port), writew(val, addr));
}
void iowrite16be(u16 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
}
void iowrite32(u32 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, outl(val,port), writel(val, addr));
}
void iowrite32be(u32 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
}
EXPORT_SYMBOL(iowrite8);
@@ -239,24 +263,32 @@ static void pio_write64be_hi_lo(u64 val, unsigned long port)
void iowrite64_lo_hi(u64 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, pio_write64_lo_hi(val, port),
writeq(val, addr));
}
void iowrite64_hi_lo(u64 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, pio_write64_hi_lo(val, port),
writeq(val, addr));
}
void iowrite64be_lo_hi(u64 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, pio_write64be_lo_hi(val, port),
mmio_write64be(val, addr));
}
void iowrite64be_hi_lo(u64 val, void __iomem *addr)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(&val, sizeof(val));
IO_COND(addr, pio_write64be_hi_lo(val, port),
mmio_write64be(val, addr));
}
@@ -328,14 +360,20 @@ static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
+ /* KMSAN must treat values read from devices as initialized. */
+ kmsan_unpoison_memory(dst, count);
}
void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
+ /* KMSAN must treat values read from devices as initialized. */
+ kmsan_unpoison_memory(dst, count * 2);
}
void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
{
IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
+ /* KMSAN must treat values read from devices as initialized. */
+ kmsan_unpoison_memory(dst, count * 4);
}
EXPORT_SYMBOL(ioread8_rep);
EXPORT_SYMBOL(ioread16_rep);
@@ -343,14 +381,20 @@ EXPORT_SYMBOL(ioread32_rep);
void iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(src, count);
IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
}
void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(src, count * 2);
IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
}
void iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
{
+ /* Make sure uninitialized memory isn't copied to devices. */
+ kmsan_check_memory(src, count * 4);
IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
}
EXPORT_SYMBOL(iowrite8_rep);