From: Darrick J. Wong <djwong@xxxxxxxxxx>
Enhance mkfs and xfs_repair to run the crc32c self test when they start
up, and refuse to continue if the self test fails. We don't want to
format a filesystem if the checksum algorithm produces incorrect
results, and we especially don't want repair to tear a filesystem apart
because it thinks the checksum is wrong.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
io/crc32cselftest.c | 2 +-
libfrog/crc32.c | 2 +-
libfrog/crc32cselftest.h | 21 ++++++++++++++-------
man/man8/mkfs.xfs.8 | 4 ++++
man/man8/xfs_repair.8 | 4 ++++
mkfs/xfs_mkfs.c | 8 ++++++++
repair/init.c | 5 +++++
7 files changed, 37 insertions(+), 9 deletions(-)
diff --git a/io/crc32cselftest.c b/io/crc32cselftest.c
index f8f757f6..49eb5b6d 100644
--- a/io/crc32cselftest.c
+++ b/io/crc32cselftest.c
@@ -16,7 +16,7 @@ crc32cselftest_f(
int argc,
char **argv)
{
- return crc32c_test() != 0;
+ return crc32c_test(0) != 0;
}
static const cmdinfo_t crc32cselftest_cmd = {
diff --git a/libfrog/crc32.c b/libfrog/crc32.c
index 6a273b71..2499615d 100644
--- a/libfrog/crc32.c
+++ b/libfrog/crc32.c
@@ -202,7 +202,7 @@ int main(int argc, char **argv)
printf("CRC_LE_BITS = %d\n", CRC_LE_BITS);
- errors = crc32c_test();
+ errors = crc32c_test(0);
return errors != 0;
}
diff --git a/libfrog/crc32cselftest.h b/libfrog/crc32cselftest.h
index 08284153..447a7f7d 100644
--- a/libfrog/crc32cselftest.h
+++ b/libfrog/crc32cselftest.h
@@ -661,18 +661,22 @@ static struct crc_test {
{0xb18a0319, 0x00000026, 0x000007db, 0x9dc0bb48},
};
+/* Don't print anything to stdout. */
+#define CRC32CTEST_QUIET (1U << 0)
+
static int
-crc32c_test(void)
+crc32c_test(
+ unsigned int flags)
{
- int i;
- int errors = 0;
- int bytes = 0;
- struct timeval start, stop;
- uint64_t usec;
+ int i;
+ int errors = 0;
+ int bytes = 0;
+ struct timeval start, stop;
+ uint64_t usec;
/* keep static to prevent cache warming code from
* getting eliminated by the compiler */
- static uint32_t crc;
+ static uint32_t crc;
/* pre-warm the cache */
for (i = 0; i < 100; i++) {
@@ -693,6 +697,9 @@ crc32c_test(void)
usec = stop.tv_usec - start.tv_usec +
1000000 * (stop.tv_sec - start.tv_sec);
+ if (flags & CRC32CTEST_QUIET)
+ return errors;
+
if (errors)
printf("crc32c: %d self tests failed\n", errors);
else {
diff --git a/man/man8/mkfs.xfs.8 b/man/man8/mkfs.xfs.8
index a7f70285..880e949b 100644
--- a/man/man8/mkfs.xfs.8
+++ b/man/man8/mkfs.xfs.8
@@ -121,6 +121,10 @@ If the size of the block or sector is not specified, the default sizes
.PP
Many feature options allow an optional argument of 0 or 1, to explicitly
disable or enable the functionality.
+
+The correctness of the crc32c checksum implementation will be tested
+before formatting the filesystem.
+If the test fails, the format will abort.
.SH OPTIONS
Options may be specified either on the command line or in a configuration file.
Not all command line options can be specified in configuration files; only the
diff --git a/man/man8/xfs_repair.8 b/man/man8/xfs_repair.8
index cc6a2be8..6625b47a 100644
--- a/man/man8/xfs_repair.8
+++ b/man/man8/xfs_repair.8
@@ -184,6 +184,10 @@ usual 0. This option cannot be used together with
.B \-V
Prints the version number and exits.
.SS Checks Performed
+The correctness of the crc32c checksum implementation will be tested
+before examining the filesystem.
+If the test fails, the program will abort.
+
Inconsistencies corrected include the following:
.IP 1.
Inode and inode blockmap (addressing) checks:
diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 057b3b09..3a41e17f 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -10,6 +10,7 @@
#include "libxcmd.h"
#include "libfrog/fsgeom.h"
#include "libfrog/convert.h"
+#include "libfrog/crc32cselftest.h"
#include "proto.h"
#include <ini.h>
@@ -4044,6 +4045,13 @@ main(
exit(0);
}
+ /* Make sure our checksum algorithm really works. */
+ if (crc32c_test(CRC32CTEST_QUIET) != 0) {
+ fprintf(stderr,
+ _("crc32c self-test failed, will not create a filesystem here.\n"));
+ return 1;
+ }
+
/*
* All values have been validated, discard the old device layout.
*/
diff --git a/repair/init.c b/repair/init.c
index 55f226e9..3a320b4f 100644
--- a/repair/init.c
+++ b/repair/init.c
@@ -14,6 +14,7 @@
#include "bmap.h"
#include "incore.h"
#include "prefetch.h"
+#include "libfrog/crc32cselftest.h"
#include <sys/resource.h>
static void
@@ -100,4 +101,8 @@ _("Unmount or use the dangerous (-d) option to repair a read-only mounted filesy
ts_create();
increase_rlimit();
pftrace_init();
+
+ if (crc32c_test(CRC32CTEST_QUIET) != 0)
+ do_error(
+ _("crc32c self-test failed, will not examine filesystem.\n"));
}
