diff options
| author | Ryan Moeller <[email protected]> | 2020-03-16 14:56:29 -0400 |
|---|---|---|
| committer | GitHub <[email protected]> | 2020-03-16 11:56:29 -0700 |
| commit | 4d32abaa874db06ec84aeefafa1354548f91d650 (patch) | |
| tree | d198dcc0c8522f04df7455ba6640595c94234f26 | |
| parent | 7261fc2e8136f99b89851fa853f7862db45437c3 (diff) | |
libzfs: Fix bounds checks for float parsing
UINT64_MAX is not exactly representable as a double.
The closest representation is UINT64_MAX + 1, so we can use a >=
comparison instead of > for the bounds check.
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Ryan Moeller <[email protected]>
Closes #10127
| -rw-r--r-- | cmd/ztest/ztest.c | 7 | ||||
| -rw-r--r-- | lib/libzfs/libzfs_util.c | 7 |
2 files changed, 12 insertions, 2 deletions
diff --git a/cmd/ztest/ztest.c b/cmd/ztest/ztest.c index e4b0f61f8..92b46c296 100644 --- a/cmd/ztest/ztest.c +++ b/cmd/ztest/ztest.c @@ -648,7 +648,12 @@ nicenumtoull(const char *buf) } else if (end[0] == '.') { double fval = strtod(buf, &end); fval *= pow(2, str2shift(end)); - if (fval > UINT64_MAX) { + /* + * UINT64_MAX is not exactly representable as a double. + * The closest representation is UINT64_MAX + 1, so we + * use a >= comparison instead of > for the bounds check. + */ + if (fval >= (double)UINT64_MAX) { (void) fprintf(stderr, "ztest: value too large: %s\n", buf); usage(B_FALSE); diff --git a/lib/libzfs/libzfs_util.c b/lib/libzfs/libzfs_util.c index a8e9ac9cb..c6debd576 100644 --- a/lib/libzfs/libzfs_util.c +++ b/lib/libzfs/libzfs_util.c @@ -1411,7 +1411,12 @@ zfs_nicestrtonum(libzfs_handle_t *hdl, const char *value, uint64_t *num) fval *= pow(2, shift); - if (fval > UINT64_MAX) { + /* + * UINT64_MAX is not exactly representable as a double. + * The closest representation is UINT64_MAX + 1, so we + * use a >= comparison instead of > for the bounds check. + */ + if (fval >= (double)UINT64_MAX) { if (hdl) zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "numeric value is too large")); |