mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-22 09:34:56 +02:00
Daniel Borkmann
211bf9cf17
Add a test which attempts to call bpf_check_mtu() and writes the MTU into .rodata section of the BPF program, and for comparison this adds test cases also for .bss and .data section again. The bpf_check_mtu() is a bit more special in that the passed mtu argument is read and written by the helper (instead of just written to). Assert that writes into .rodata remain rejected by the verifier. # ./vmtest.sh -- ./test_progs -t verifier_const [...] ./test_progs -t verifier_const [ 1.657367] bpf_testmod: loading out-of-tree module taints kernel. [ 1.657773] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel #473/1 verifier_const/rodata/strtol: write rejected:OK #473/2 verifier_const/bss/strtol: write accepted:OK #473/3 verifier_const/data/strtol: write accepted:OK #473/4 verifier_const/rodata/mtu: write rejected:OK #473/5 verifier_const/bss/mtu: write accepted:OK #473/6 verifier_const/data/mtu: write accepted:OK #473 verifier_const:OK [...] Summary: 2/10 PASSED, 0 SKIPPED, 0 FAILED For comparison, without the MEM_UNINIT on bpf_check_mtu's proto: # ./vmtest.sh -- ./test_progs -t verifier_const [...] #473/3 verifier_const/data/strtol: write accepted:OK run_subtest:PASS:obj_open_mem 0 nsec run_subtest:FAIL:unexpected_load_success unexpected success: 0 #473/4 verifier_const/rodata/mtu: write rejected:FAIL #473/5 verifier_const/bss/mtu: write accepted:OK #473/6 verifier_const/data/mtu: write accepted:OK #473 verifier_const:FAIL [...] Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20240913191754.13290-9-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.