GCC 7.1 fixes

GCC 7.1 with will warn when we're not checking the snprintf()
return code in cases where the buffer could be truncated. This
patch either checks the snprintf return code (where applicable),
or simply disables the warnings (ztest.c).

Reviewed-by: Chunwei Chen <david.chen@osnexus.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes 
This commit is contained in:
Tony Hutter 2017-06-28 10:05:16 -07:00
parent 3e297b90f5
commit b88f4d7ba7
8 changed files with 70 additions and 25 deletions

View File

@ -1,6 +1,8 @@
include $(top_srcdir)/config/Rules.am
AM_CFLAGS += $(DEBUG_STACKFLAGS) $(FRAME_LARGER_THAN)
# -Wnoformat-truncation to get rid of compiler warning for unchecked
# truncating snprintfs on gcc 7.1.1.
AM_CFLAGS += $(DEBUG_STACKFLAGS) $(FRAME_LARGER_THAN) $(NO_FORMAT_TRUNCATION)
DEFAULT_INCLUDES += \
-I$(top_srcdir)/include \

View File

@ -0,0 +1,22 @@
dnl #
dnl # Check if gcc supports -Wno-format-truncation option.
dnl #
AC_DEFUN([ZFS_AC_CONFIG_USER_NO_FORMAT_TRUNCATION], [
AC_MSG_CHECKING([for -Wno-format-truncation support])
saved_flags="$CFLAGS"
CFLAGS="$CFLAGS -Wno-format-truncation"
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [])],
[
NO_FORMAT_TRUNCATION=-Wno-format-truncation
AC_MSG_RESULT([yes])
],
[
NO_FORMAT_TRUNCATION=
AC_MSG_RESULT([no])
])
CFLAGS="$saved_flags"
AC_SUBST([NO_FORMAT_TRUNCATION])
])

View File

@ -15,6 +15,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER], [
ZFS_AC_CONFIG_USER_RUNSTATEDIR
ZFS_AC_CONFIG_USER_MAKEDEV_IN_SYSMACROS
ZFS_AC_CONFIG_USER_MAKEDEV_IN_MKDEV
ZFS_AC_CONFIG_USER_NO_FORMAT_TRUNCATION
dnl #
dnl # Checks for library functions
AC_CHECK_FUNCS([mlockall])

View File

@ -40,6 +40,20 @@ libspl_assert(const char *buf, const char *file, const char *func, int line)
abort();
}
/* printf version of libspl_assert */
static inline void
libspl_assertf(const char *file, const char *func, int line, char *format, ...)
{
va_list args;
va_start(args, format);
vfprintf(stderr, format, args);
fprintf(stderr, "\n");
fprintf(stderr, "ASSERT at %s:%d:%s()", file, line, func);
va_end(args);
abort();
}
#ifdef verify
#undef verify
#endif
@ -55,13 +69,9 @@ libspl_assert(const char *buf, const char *file, const char *func, int line)
do { \
const TYPE __left = (TYPE)(LEFT); \
const TYPE __right = (TYPE)(RIGHT); \
if (!(__left OP __right)) { \
char *__buf = alloca(256); \
(void) snprintf(__buf, 256, \
"%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT, \
(u_longlong_t)__left, #OP, (u_longlong_t)__right); \
libspl_assert(__buf, __FILE__, __FUNCTION__, __LINE__); \
} \
if (!(__left OP __right)) \
libspl_assertf(__FILE__, __FUNCTION__, __LINE__, \
"%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT); \
} while (0)
#define VERIFY3S(x, y, z) VERIFY3_IMPL(x, y, z, int64_t)

View File

@ -3315,8 +3315,9 @@ zfs_check_snap_cb(zfs_handle_t *zhp, void *arg)
char name[ZFS_MAXNAMELEN];
int rv = 0;
(void) snprintf(name, sizeof (name),
"%s@%s", zhp->zfs_name, dd->snapname);
if (snprintf(name, sizeof (name), "%s@%s", zhp->zfs_name,
dd->snapname) >= sizeof (name))
return (EINVAL);
if (lzc_exists(name))
verify(nvlist_add_boolean(dd->nvl, name) == 0);
@ -3534,8 +3535,9 @@ zfs_snapshot_cb(zfs_handle_t *zhp, void *arg)
int rv = 0;
if (zfs_prop_get_int(zhp, ZFS_PROP_INCONSISTENT) == 0) {
(void) snprintf(name, sizeof (name),
"%s@%s", zfs_get_name(zhp), sd->sd_snapname);
if (snprintf(name, sizeof (name), "%s@%s", zfs_get_name(zhp),
sd->sd_snapname) >= sizeof (name))
return (EINVAL);
fnvlist_add_boolean(sd->sd_nvl, name);
@ -4257,8 +4259,9 @@ zfs_hold_one(zfs_handle_t *zhp, void *arg)
char name[ZFS_MAXNAMELEN];
int rv = 0;
(void) snprintf(name, sizeof (name),
"%s@%s", zhp->zfs_name, ha->snapname);
if (snprintf(name, sizeof (name), "%s@%s", zhp->zfs_name,
ha->snapname) >= sizeof (name))
return (EINVAL);
if (lzc_exists(name))
fnvlist_add_string(ha->nvl, name, ha->tag);
@ -4377,8 +4380,11 @@ zfs_release_one(zfs_handle_t *zhp, void *arg)
int rv = 0;
nvlist_t *existing_holds;
(void) snprintf(name, sizeof (name),
"%s@%s", zhp->zfs_name, ha->snapname);
if (snprintf(name, sizeof (name), "%s@%s", zhp->zfs_name,
ha->snapname) >= sizeof (name)) {
ha->error = EINVAL;
rv = EINVAL;
}
if (lzc_get_holds(name, &existing_holds) != 0) {
ha->error = ENOENT;

View File

@ -204,8 +204,11 @@ zfs_iter_bookmarks(zfs_handle_t *zhp, zfs_iter_f func, void *data)
bmark_name = nvpair_name(pair);
bmark_props = fnvpair_value_nvlist(pair);
(void) snprintf(name, sizeof (name), "%s#%s", zhp->zfs_name,
bmark_name);
if (snprintf(name, sizeof (name), "%s#%s", zhp->zfs_name,
bmark_name) >= sizeof (name)) {
err = EINVAL;
goto out;
}
nzhp = make_bookmark_handle(zhp, name, bmark_props);
if (nzhp == NULL)

View File

@ -1487,9 +1487,13 @@ zfs_send(zfs_handle_t *zhp, const char *fromsnap, const char *tosnap,
drr_versioninfo, DMU_COMPOUNDSTREAM);
DMU_SET_FEATUREFLAGS(drr.drr_u.drr_begin.
drr_versioninfo, featureflags);
(void) snprintf(drr.drr_u.drr_begin.drr_toname,
if (snprintf(drr.drr_u.drr_begin.drr_toname,
sizeof (drr.drr_u.drr_begin.drr_toname),
"%s@%s", zhp->zfs_name, tosnap);
"%s@%s", zhp->zfs_name, tosnap) >=
sizeof (drr.drr_u.drr_begin.drr_toname)) {
err = EINVAL;
goto stderr_out;
}
drr.drr_payloadlen = buflen;
err = cksum_and_write(&drr, sizeof (drr), &zc, outfd);

View File

@ -1615,14 +1615,12 @@ zvol_rename_minors_impl(const char *oldname, const char *newname)
{
zvol_state_t *zv, *zv_next;
int oldnamelen, newnamelen;
char *name;
if (zvol_inhibit_dev)
return;
oldnamelen = strlen(oldname);
newnamelen = strlen(newname);
name = kmem_alloc(MAXNAMELEN, KM_SLEEP);
mutex_enter(&zvol_state_lock);
@ -1638,16 +1636,15 @@ zvol_rename_minors_impl(const char *oldname, const char *newname)
} else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 &&
(zv->zv_name[oldnamelen] == '/' ||
zv->zv_name[oldnamelen] == '@')) {
snprintf(name, MAXNAMELEN, "%s%c%s", newname,
char *name = kmem_asprintf("%s%c%s", newname,
zv->zv_name[oldnamelen],
zv->zv_name + oldnamelen + 1);
zvol_rename_minor(zv, name);
kmem_free(name, strlen(name + 1));
}
}
mutex_exit(&zvol_state_lock);
kmem_free(name, MAXNAMELEN);
}
typedef struct zvol_snapdev_cb_arg {