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authorLinus Torvalds <torvalds@linux-foundation.org>2022-08-05 14:03:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-08-05 14:03:11 -0700
commit79b7e67bb9747e621ff1b646a125fbea26e08d56 (patch)
tree0f726e0c9ef34217fbc7bc3f6a7a79bea18fe17d /arch/um
parent4d5398a3ec060c1e3094097e52a19a4d0013c0e0 (diff)
parentaf3e16101cee95efaa72095fe06c15ec0b8eb195 (diff)
Merge tag 'for-linus-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger: - KASAN support for x86_64 - noreboot command line option, just like qemu's -no-reboot - Various fixes and cleanups * tag 'for-linus-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: include sys/types.h for size_t um: Replace to_phys() and to_virt() with less generic function names um: Add missing apply_returns() um: add "noreboot" command line option for PANIC_TIMEOUT=-1 setups um: include linux/stddef.h for __always_inline UML: add support for KASAN under x86_64 mm: Add PAGE_ALIGN_DOWN macro um: random: Don't initialise hwrng struct with zero um: remove unused mm_copy_segments um: remove unused variable um: Remove straying parenthesis um: x86: print RIP with symbol arch: um: Fix build for statically linked UML w/ constructors x86/um: Kconfig: Fix indentation um/drivers: Kconfig: Fix indentation um: Kconfig: Fix indentation
Diffstat (limited to 'arch/um')
-rw-r--r--arch/um/Kconfig17
-rw-r--r--arch/um/drivers/Kconfig54
-rw-r--r--arch/um/drivers/random.c2
-rw-r--r--arch/um/include/asm/common.lds.S2
-rw-r--r--arch/um/include/asm/kasan.h37
-rw-r--r--arch/um/include/asm/processor-generic.h5
-rw-r--r--arch/um/include/asm/xor.h2
-rw-r--r--arch/um/include/shared/user.h3
-rw-r--r--arch/um/kernel/dyn.lds.S6
-rw-r--r--arch/um/kernel/mem.c19
-rw-r--r--arch/um/kernel/stacktrace.c2
-rw-r--r--arch/um/kernel/uml.lds.S1
-rw-r--r--arch/um/os-Linux/mem.c22
-rw-r--r--arch/um/os-Linux/skas/process.c17
-rw-r--r--arch/um/os-Linux/umid.c3
-rw-r--r--arch/um/os-Linux/user_syms.c4
16 files changed, 153 insertions, 43 deletions
diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 4ec22e156a2e..78de31ac1da7 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -12,6 +12,8 @@ config UML
select ARCH_HAS_STRNLEN_USER
select ARCH_NO_PREEMPT
select HAVE_ARCH_AUDITSYSCALL
+ select HAVE_ARCH_KASAN if X86_64
+ select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
select HAVE_ARCH_SECCOMP_FILTER
select HAVE_ASM_MODVERSIONS
select HAVE_UID16
@@ -82,7 +84,7 @@ config ARCH_HAS_CACHE_LINE_SIZE
source "arch/$(HEADER_ARCH)/um/Kconfig"
config MAY_HAVE_RUNTIME_DEPS
- bool
+ bool
config STATIC_LINK
bool "Force a static link"
@@ -219,6 +221,19 @@ config UML_TIME_TRAVEL_SUPPORT
It is safe to say Y, but you probably don't need this.
+config KASAN_SHADOW_OFFSET
+ hex
+ depends on KASAN
+ default 0x100000000000
+ help
+ This is the offset at which the ~16TB of shadow memory is
+ mapped and used by KASAN for memory debugging. This can be any
+ address that has at least KASAN_SHADOW_SIZE (total address space divided
+ by 8) amount of space so that the KASAN shadow memory does not conflict
+ with anything. The default is 0x100000000000, which works even if mem is
+ set to a large value. On low-memory systems, try 0x7fff8000, as it fits
+ into the immediate of most instructions, improving performance.
+
endmenu
source "arch/um/drivers/Kconfig"
diff --git a/arch/um/drivers/Kconfig b/arch/um/drivers/Kconfig
index 914da774bd39..5903e2b598aa 100644
--- a/arch/um/drivers/Kconfig
+++ b/arch/um/drivers/Kconfig
@@ -251,37 +251,37 @@ config UML_NET_VECTOR
depends on UML_NET
select MAY_HAVE_RUNTIME_DEPS
help
- This User-Mode Linux network driver uses multi-message send
- and receive functions. The host running the UML guest must have
- a linux kernel version above 3.0 and a libc version > 2.13.
- This driver provides tap, raw, gre and l2tpv3 network transports
- with up to 4 times higher network throughput than the UML network
- drivers.
+ This User-Mode Linux network driver uses multi-message send
+ and receive functions. The host running the UML guest must have
+ a linux kernel version above 3.0 and a libc version > 2.13.
+ This driver provides tap, raw, gre and l2tpv3 network transports
+ with up to 4 times higher network throughput than the UML network
+ drivers.
config UML_NET_VDE
bool "VDE transport (obsolete)"
depends on UML_NET
select MAY_HAVE_RUNTIME_DEPS
help
- This User-Mode Linux network transport allows one or more running
- UMLs on a single host to communicate with each other and also
- with the rest of the world using Virtual Distributed Ethernet,
- an improved fork of uml_switch.
+ This User-Mode Linux network transport allows one or more running
+ UMLs on a single host to communicate with each other and also
+ with the rest of the world using Virtual Distributed Ethernet,
+ an improved fork of uml_switch.
- You must have libvdeplug installed in order to build the vde
- transport into UML.
+ You must have libvdeplug installed in order to build the vde
+ transport into UML.
- To use this form of networking, you will need to run vde_switch
- on the host.
+ To use this form of networking, you will need to run vde_switch
+ on the host.
- For more information, see <http://wiki.virtualsquare.org/>
- That site has a good overview of what VDE is and also examples
- of the UML command line to use to enable VDE networking.
+ For more information, see <http://wiki.virtualsquare.org/>
+ That site has a good overview of what VDE is and also examples
+ of the UML command line to use to enable VDE networking.
- NOTE: THIS TRANSPORT IS DEPRECATED AND WILL BE REMOVED SOON!!! Please
- migrate to UML_NET_VECTOR.
+ NOTE: THIS TRANSPORT IS DEPRECATED AND WILL BE REMOVED SOON!!! Please
+ migrate to UML_NET_VECTOR.
- If unsure, say N.
+ If unsure, say N.
config UML_NET_MCAST
bool "Multicast transport (obsolete)"
@@ -311,19 +311,19 @@ config UML_NET_PCAP
depends on UML_NET
select MAY_HAVE_RUNTIME_DEPS
help
- The pcap transport makes a pcap packet stream on the host look
- like an ethernet device inside UML. This is useful for making
- UML act as a network monitor for the host. You must have libcap
- installed in order to build the pcap transport into UML.
+ The pcap transport makes a pcap packet stream on the host look
+ like an ethernet device inside UML. This is useful for making
+ UML act as a network monitor for the host. You must have libcap
+ installed in order to build the pcap transport into UML.
For more information, see
<http://user-mode-linux.sourceforge.net/old/networking.html> That site
has examples of the UML command line to use to enable this option.
- NOTE: THIS TRANSPORT IS DEPRECATED AND WILL BE REMOVED SOON!!! Please
- migrate to UML_NET_VECTOR.
+ NOTE: THIS TRANSPORT IS DEPRECATED AND WILL BE REMOVED SOON!!! Please
+ migrate to UML_NET_VECTOR.
- If unsure, say N.
+ If unsure, say N.
config UML_NET_SLIRP
bool "SLiRP transport (obsolete)"
diff --git a/arch/um/drivers/random.c b/arch/um/drivers/random.c
index 433a3f8f2ef3..32b3341fe970 100644
--- a/arch/um/drivers/random.c
+++ b/arch/um/drivers/random.c
@@ -28,7 +28,7 @@
* protects against a module being loaded twice at the same time.
*/
static int random_fd = -1;
-static struct hwrng hwrng = { 0, };
+static struct hwrng hwrng;
static DECLARE_COMPLETION(have_data);
static int rng_dev_read(struct hwrng *rng, void *buf, size_t max, bool block)
diff --git a/arch/um/include/asm/common.lds.S b/arch/um/include/asm/common.lds.S
index eca6c452a41b..fd481ac371de 100644
--- a/arch/um/include/asm/common.lds.S
+++ b/arch/um/include/asm/common.lds.S
@@ -83,6 +83,8 @@
}
.init_array : {
__init_array_start = .;
+ *(.kasan_init)
+ *(.init_array.*)
*(.init_array)
__init_array_end = .;
}
diff --git a/arch/um/include/asm/kasan.h b/arch/um/include/asm/kasan.h
new file mode 100644
index 000000000000..0d6547f4ec85
--- /dev/null
+++ b/arch/um/include/asm/kasan.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_UM_KASAN_H
+#define __ASM_UM_KASAN_H
+
+#include <linux/init.h>
+#include <linux/const.h>
+
+#define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
+
+/* used in kasan_mem_to_shadow to divide by 8 */
+#define KASAN_SHADOW_SCALE_SHIFT 3
+
+#ifdef CONFIG_X86_64
+#define KASAN_HOST_USER_SPACE_END_ADDR 0x00007fffffffffffUL
+/* KASAN_SHADOW_SIZE is the size of total address space divided by 8 */
+#define KASAN_SHADOW_SIZE ((KASAN_HOST_USER_SPACE_END_ADDR + 1) >> \
+ KASAN_SHADOW_SCALE_SHIFT)
+#else
+#error "KASAN_SHADOW_SIZE is not defined for this sub-architecture"
+#endif /* CONFIG_X86_64 */
+
+#define KASAN_SHADOW_START (KASAN_SHADOW_OFFSET)
+#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE)
+
+#ifdef CONFIG_KASAN
+void kasan_init(void);
+void kasan_map_memory(void *start, unsigned long len);
+extern int kasan_um_is_ready;
+
+#ifdef CONFIG_STATIC_LINK
+#define kasan_arch_is_ready() (kasan_um_is_ready)
+#endif
+#else
+static inline void kasan_init(void) { }
+#endif /* CONFIG_KASAN */
+
+#endif /* __ASM_UM_KASAN_H */
diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h
index 6a4fe8b4e686..d0fc1862da95 100644
--- a/arch/um/include/asm/processor-generic.h
+++ b/arch/um/include/asm/processor-generic.h
@@ -59,11 +59,6 @@ static inline void release_thread(struct task_struct *task)
{
}
-static inline void mm_copy_segments(struct mm_struct *from_mm,
- struct mm_struct *new_mm)
-{
-}
-
/*
* User space process size: 3GB (default).
*/
diff --git a/arch/um/include/asm/xor.h b/arch/um/include/asm/xor.h
index 22b39de73c24..647fae200c5d 100644
--- a/arch/um/include/asm/xor.h
+++ b/arch/um/include/asm/xor.h
@@ -18,7 +18,7 @@
#undef XOR_SELECT_TEMPLATE
/* pick an arbitrary one - measuring isn't possible with inf-cpu */
#define XOR_SELECT_TEMPLATE(x) \
- (time_travel_mode == TT_MODE_INFCPU ? TT_CPU_INF_XOR_DEFAULT : x))
+ (time_travel_mode == TT_MODE_INFCPU ? TT_CPU_INF_XOR_DEFAULT : x)
#endif
#endif
diff --git a/arch/um/include/shared/user.h b/arch/um/include/shared/user.h
index dd4badffdeb3..bda66e5a9d4e 100644
--- a/arch/um/include/shared/user.h
+++ b/arch/um/include/shared/user.h
@@ -16,11 +16,12 @@
*/
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-/* This is to get size_t */
+/* This is to get size_t and NULL */
#ifndef __UM_HOST__
#include <linux/types.h>
#else
#include <stddef.h>
+#include <sys/types.h>
#endif
extern void panic(const char *fmt, ...)
diff --git a/arch/um/kernel/dyn.lds.S b/arch/um/kernel/dyn.lds.S
index 2f2a8ce92f1e..2b7fc5b54164 100644
--- a/arch/um/kernel/dyn.lds.S
+++ b/arch/um/kernel/dyn.lds.S
@@ -109,7 +109,11 @@ SECTIONS
be empty, which isn't pretty. */
. = ALIGN(32 / 8);
.preinit_array : { *(.preinit_array) }
- .init_array : { *(.init_array) }
+ .init_array : {
+ *(.kasan_init)
+ *(.init_array.*)
+ *(.init_array)
+ }
.fini_array : { *(.fini_array) }
.data : {
INIT_TASK_DATA(KERNEL_STACK_SIZE)
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 15295c3237a0..276a1f0b91f1 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -18,6 +18,25 @@
#include <kern_util.h>
#include <mem_user.h>
#include <os.h>
+#include <linux/sched/task.h>
+
+#ifdef CONFIG_KASAN
+int kasan_um_is_ready;
+void kasan_init(void)
+{
+ /*
+ * kasan_map_memory will map all of the required address space and
+ * the host machine will allocate physical memory as necessary.
+ */
+ kasan_map_memory((void *)KASAN_SHADOW_START, KASAN_SHADOW_SIZE);
+ init_task.kasan_depth = 0;
+ kasan_um_is_ready = true;
+}
+
+static void (*kasan_init_ptr)(void)
+__section(".kasan_init") __used
+= kasan_init;
+#endif
/* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */
unsigned long *empty_zero_page = NULL;
diff --git a/arch/um/kernel/stacktrace.c b/arch/um/kernel/stacktrace.c
index 86df52168bd9..fd3b61b3d4d2 100644
--- a/arch/um/kernel/stacktrace.c
+++ b/arch/um/kernel/stacktrace.c
@@ -27,7 +27,7 @@ void dump_trace(struct task_struct *tsk,
frame = (struct stack_frame *)bp;
while (((long) sp & (THREAD_SIZE-1)) != 0) {
- addr = *sp;
+ addr = READ_ONCE_NOCHECK(*sp);
if (__kernel_text_address(addr)) {
reliable = 0;
if ((unsigned long) sp == bp + sizeof(long)) {
diff --git a/arch/um/kernel/uml.lds.S b/arch/um/kernel/uml.lds.S
index 7a8e2b123e29..71a59b8adbdc 100644
--- a/arch/um/kernel/uml.lds.S
+++ b/arch/um/kernel/uml.lds.S
@@ -95,6 +95,7 @@ SECTIONS
}
.got : { *(.got.plt) *(.got) }
+ .eh_frame : { KEEP (*(.eh_frame)) }
.dynamic : { *(.dynamic) }
.tdata : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
.tbss : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) }
diff --git a/arch/um/os-Linux/mem.c b/arch/um/os-Linux/mem.c
index 3c1b77474d2d..8530b2e08604 100644
--- a/arch/um/os-Linux/mem.c
+++ b/arch/um/os-Linux/mem.c
@@ -17,6 +17,28 @@
#include <init.h>
#include <os.h>
+/*
+ * kasan_map_memory - maps memory from @start with a size of @len.
+ * The allocated memory is filled with zeroes upon success.
+ * @start: the start address of the memory to be mapped
+ * @len: the length of the memory to be mapped
+ *
+ * This function is used to map shadow memory for KASAN in uml
+ */
+void kasan_map_memory(void *start, size_t len)
+{
+ if (mmap(start,
+ len,
+ PROT_READ|PROT_WRITE,
+ MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE|MAP_NORESERVE,
+ -1,
+ 0) == MAP_FAILED) {
+ os_info("Couldn't allocate shadow memory: %s\n.",
+ strerror(errno));
+ exit(1);
+ }
+}
+
/* Set by make_tempfile() during early boot. */
static char *tempdir = NULL;
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index c316c993a949..b24db6017ded 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -5,6 +5,7 @@
*/
#include <stdlib.h>
+#include <stdbool.h>
#include <unistd.h>
#include <sched.h>
#include <errno.h>
@@ -707,10 +708,24 @@ void halt_skas(void)
UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT);
}
+static bool noreboot;
+
+static int __init noreboot_cmd_param(char *str, int *add)
+{
+ noreboot = true;
+ return 0;
+}
+
+__uml_setup("noreboot", noreboot_cmd_param,
+"noreboot\n"
+" Rather than rebooting, exit always, akin to QEMU's -no-reboot option.\n"
+" This is useful if you're using CONFIG_PANIC_TIMEOUT in order to catch\n"
+" crashes in CI\n");
+
void reboot_skas(void)
{
block_signals_trace();
- UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT);
+ UML_LONGJMP(&initial_jmpbuf, noreboot ? INIT_JMP_HALT : INIT_JMP_REBOOT);
}
void __switch_mm(struct mm_id *mm_idp)
diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c
index a3dd61521d24..7a1abb829930 100644
--- a/arch/um/os-Linux/umid.c
+++ b/arch/um/os-Linux/umid.c
@@ -136,7 +136,7 @@ out:
static inline int is_umdir_used(char *dir)
{
char pid[sizeof("nnnnnnnnn")], *end, *file;
- int dead, fd, p, n, err;
+ int fd, p, n, err;
size_t filelen = strlen(dir) + sizeof("/pid") + 1;
file = malloc(filelen);
@@ -145,7 +145,6 @@ static inline int is_umdir_used(char *dir)
snprintf(file, filelen, "%s/pid", dir);
- dead = 0;
fd = open(file, O_RDONLY);
if (fd < 0) {
fd = -errno;
diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c
index 715594fe5719..cb667c9225ab 100644
--- a/arch/um/os-Linux/user_syms.c
+++ b/arch/um/os-Linux/user_syms.c
@@ -27,10 +27,10 @@ EXPORT_SYMBOL(strstr);
#ifndef __x86_64__
extern void *memcpy(void *, const void *, size_t);
EXPORT_SYMBOL(memcpy);
-#endif
-
EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(memset);
+#endif
+
EXPORT_SYMBOL(printf);
/* Here, instead, I can provide a fake prototype. Yes, someone cares: genksyms.