proc: fix /proc/*/map_files lookup some more

I totally forgot that _parse_integer() accepts arbitrary amount of
leading zeroes leading to the following lookups:

		OK
	# readlink /proc/1/map_files/56427ecba000-56427eddc000
	/lib/systemd/systemd

		bogus
	# readlink /proc/1/map_files/00000000000056427ecba000-56427eddc000
	/lib/systemd/systemd
	# readlink /proc/1/map_files/56427ecba000-00000000000056427eddc000
	/lib/systemd/systemd

Link: http://lkml.kernel.org/r/20180303215130.GA23480@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index e9e7652..d413a13 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1913,6 +1913,8 @@ static int dname_to_vma_addr(struct dentry *dentry,
        unsigned long long sval, eval;
        unsigned int len;
 
+       if (str[0] == '0' && str[1] != '-')
+               return -EINVAL;
        len = _parse_integer(str, 16, &sval);
        if (len & KSTRTOX_OVERFLOW)
                return -EINVAL;
@@ -1924,6 +1926,8 @@ static int dname_to_vma_addr(struct dentry *dentry,
                return -EINVAL;
        str++;
 
+       if (str[0] == '0' && str[1])
+               return -EINVAL;
        len = _parse_integer(str, 16, &eval);
        if (len & KSTRTOX_OVERFLOW)
                return -EINVAL;

diff --git a/tools/testing/selftests/proc/.gitignore b/tools/testing/selftests/proc/.gitignore
index c648b27..e3ceb19 100644 (file)
--- a/tools/testing/selftests/proc/.gitignore
+++ b/tools/testing/selftests/proc/.gitignore
@@ -1,2 +1,4 @@
-/proc-self-mem
+/proc-self-map-files-001
+/proc-self-map-files-002
 /proc-self-syscall
+/proc-self-wchan

diff --git a/tools/testing/selftests/proc/Makefile b/tools/testing/selftests/proc/Makefile
index ad20520..1a0ce32 100644 (file)
--- a/tools/testing/selftests/proc/Makefile
+++ b/tools/testing/selftests/proc/Makefile
@@ -1,6 +1,8 @@
 CFLAGS += -Wall -O2
 
 TEST_GEN_PROGS :=
+TEST_GEN_PROGS += proc-self-map-files-001
+TEST_GEN_PROGS += proc-self-map-files-002
 TEST_GEN_PROGS += proc-self-syscall
 TEST_GEN_PROGS += proc-self-wchan
 

diff --git a/tools/testing/selftests/proc/proc-self-map-files-001.c b/tools/testing/selftests/proc/proc-self-map-files-001.c
new file mode 100644 (file)
index 0000000..af1d0a6
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-self-map-files-001.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test readlink /proc/self/map_files/... */
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+
+static void pass(const char *fmt, unsigned long a, unsigned long b)
+{
+       char name[64];
+       char buf[64];
+
+       snprintf(name, sizeof(name), fmt, a, b);
+       if (readlink(name, buf, sizeof(buf)) == -1)
+               exit(1);
+}
+
+static void fail(const char *fmt, unsigned long a, unsigned long b)
+{
+       char name[64];
+       char buf[64];
+
+       snprintf(name, sizeof(name), fmt, a, b);
+       if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT)
+               return;
+       exit(1);
+}
+
+int main(void)
+{
+       const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE);
+       void *p;
+       int fd;
+       unsigned long a, b;
+
+       fd = open("/dev/zero", O_RDONLY);
+       if (fd == -1)
+               return 1;
+
+       p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE, fd, 0);
+       if (p == MAP_FAILED)
+               return 1;
+
+       a = (unsigned long)p;
+       b = (unsigned long)p + PAGE_SIZE;
+
+       pass("/proc/self/map_files/%lx-%lx", a, b);
+       fail("/proc/self/map_files/ %lx-%lx", a, b);
+       fail("/proc/self/map_files/%lx -%lx", a, b);
+       fail("/proc/self/map_files/%lx- %lx", a, b);
+       fail("/proc/self/map_files/%lx-%lx ", a, b);
+       fail("/proc/self/map_files/0%lx-%lx", a, b);
+       fail("/proc/self/map_files/%lx-0%lx", a, b);
+       if (sizeof(long) == 4) {
+               fail("/proc/self/map_files/100000000%lx-%lx", a, b);
+               fail("/proc/self/map_files/%lx-100000000%lx", a, b);
+       } else if (sizeof(long) == 8) {
+               fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b);
+               fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b);
+       } else
+               return 1;
+
+       return 0;
+}

diff --git a/tools/testing/selftests/proc/proc-self-map-files-002.c b/tools/testing/selftests/proc/proc-self-map-files-002.c
new file mode 100644 (file)
index 0000000..aebf4be
--- /dev/null
+++ b/tools/testing/selftests/proc/proc-self-map-files-002.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright _ 2018 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test readlink /proc/self/map_files/... with address 0. */
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+
+static void pass(const char *fmt, unsigned long a, unsigned long b)
+{
+       char name[64];
+       char buf[64];
+
+       snprintf(name, sizeof(name), fmt, a, b);
+       if (readlink(name, buf, sizeof(buf)) == -1)
+               exit(1);
+}
+
+static void fail(const char *fmt, unsigned long a, unsigned long b)
+{
+       char name[64];
+       char buf[64];
+
+       snprintf(name, sizeof(name), fmt, a, b);
+       if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT)
+               return;
+       exit(1);
+}
+
+int main(void)
+{
+       const unsigned int PAGE_SIZE = sysconf(_SC_PAGESIZE);
+       void *p;
+       int fd;
+       unsigned long a, b;
+
+       fd = open("/dev/zero", O_RDONLY);
+       if (fd == -1)
+               return 1;
+
+       p = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0);
+       if (p == MAP_FAILED) {
+               if (errno == EPERM)
+                       return 2;
+               return 1;
+       }
+
+       a = (unsigned long)p;
+       b = (unsigned long)p + PAGE_SIZE;
+
+       pass("/proc/self/map_files/%lx-%lx", a, b);
+       fail("/proc/self/map_files/ %lx-%lx", a, b);
+       fail("/proc/self/map_files/%lx -%lx", a, b);
+       fail("/proc/self/map_files/%lx- %lx", a, b);
+       fail("/proc/self/map_files/%lx-%lx ", a, b);
+       fail("/proc/self/map_files/0%lx-%lx", a, b);
+       fail("/proc/self/map_files/%lx-0%lx", a, b);
+       if (sizeof(long) == 4) {
+               fail("/proc/self/map_files/100000000%lx-%lx", a, b);
+               fail("/proc/self/map_files/%lx-100000000%lx", a, b);
+       } else if (sizeof(long) == 8) {
+               fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b);
+               fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b);
+       } else
+               return 1;
+
+       return 0;
+}