2.0.0-1.12 (Feb 27th, 2023)

Twelfth errata of the standalone userspace implementation.

This is a pre-release with limited functionality.

New features:

• The bcopy() subroutine no longer enforces that its first argument (source address) can't be an alloca()'d memory region. While this restriction is documented, it was never enforced in DTrace and the restriction has no practical reason.

• The clear() and tracemem() actions have been implemented.

• The switchrate and aggrate options have been implemented.

• The cpc and proc providers have been implemented.

• The copyout() and copyoutstr() subroutines have been implemented.

• The uregs[] built-in variable has been implemented.

Bugfixes:

• The maximum strtab size has been increased to SSIZE_MAX.

• Probe argument information is only be retrieved once per probe.

• Handling string values in alloca()'d memory has been fixed.

• The basename(), dirname(), strchr(), strrchr(), inet_ntoa() subroutines have been updated to fully support using arbitrary address pointers.

• The return value of copyin() is now a valid offset into scratchmem (native representation of a pointer to alloca()'d memory).

• The arg0 and arg1 probe arguments for profile-* and tick-* probes have been corrected. (The arg2 argument is still unimplemented.)

• The evaluation order of arguments to bcopy() has been corrected.

• Runtime bounds checking has been implemented for scalar array access.

Internal changes:

• Selection of the correct arch-dependent asm include hierarchy for building the precompiled BPF function library has been corrected.

• A few potentially unsafe calls to printf-style functions have been fixed.

• The manpage for dtrace has been moved to section 8 (System Management Commands).

• The error handling mechanism between libdtrace and consumer front-ends has been amended to allow error reporting for non-probing related issues.

• The copyinstr() subroutine has been updated to use the temporary string mechanism.

• The tracking of pointers to alloca()'d memory and pointer to DTrace managed memory has been improved, and explicit tests for it have been added to the testsuite.

• The code generator uses indirect load instructions for pointers to alloca()'d and DTrace managed memory for efficiency and to enable the BPF verifier to perform access checks.

Testsuite changes:

• The copyin*() tests are now more robust with the use of a distinct trigger.

• Various tests have been moved from XFAIL to PASS status to reflect the implementation of new features and because some bug fixes.

• Various tests were improved.

• Various new tests were added.

Known problems:

• The uregs[] built-in variable isn't supported on kernels before 5.15.