kernel/linux.git/tools/testing/selftests/resctrl, branch v6.6.132

selftests/resctrl: Protect against array overflow when reading strings

2024-12-14T19:00:01+00:00

[ Upstream commit 46058430fc5d39c114f7e1b9c6ff14c9f41bd531 ] resctrl selftests discover system properties via a variety of sysfs files. The MBM and MBA tests need to discover the event and umask with which to configure the performance event used to measure read memory bandwidth. This is done by parsing the contents of /sys/bus/event_source/devices/uncore_imc_/events/cas_count_read Similarly, the resctrl selftests discover the cache size via /sys/bus/cpu/devices/cpu/cache/index/size. Take care to do bounds checking when using fscanf() to read the contents of files into a string buffer because by default fscanf() assumes arbitrarily long strings. If the file contains more bytes than the array can accommodate then an overflow will occur. Provide a maximum field width to the conversion specifier to protect against array overflow. The maximum is one less than the array size because string input stores a terminating null byte that is not covered by the maximum field width. Signed-off-by: Reinette Chatre Reviewed-by: Ilpo Järvinen Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests/resctrl: Protect against array overrun during iMC config parsing

2024-12-09T09:31:58+00:00

[ Upstream commit 48ed4e799e8fbebae838dca404a8527763d41191 ] The MBM and MBA tests need to discover the event and umask with which to configure the performance event used to measure read memory bandwidth. This is done by parsing the /sys/bus/event_source/devices/uncore_imc_/events/cas_count_read file for each iMC instance that contains the formatted output: "event=,umask=" Parsing of cas_count_read contents is done by initializing an array of MAX_TOKENS elements with tokens (deliminated by "=,") from this file. Remove the unnecessary append of a delimiter to the string needing to be parsed. Per the strtok() man page: "delimiter bytes at the start or end of the string are ignored". This has no impact on the token placement within the array. After initialization, the actual event and umask is determined by parsing the tokens directly following the "event" and "umask" tokens respectively. Iterating through the array up to index "i < MAX_TOKENS" but then accessing index "i + 1" risks array overrun during the final iteration. Avoid array overrun by ensuring that the index used within for loop will always be valid. Fixes: 1d3f08687d76 ("selftests/resctrl: Read memory bandwidth from perf IMC counter and from resctrl file system") Signed-off-by: Reinette Chatre Reviewed-by: Ilpo Järvinen Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests/resctrl: Fix memory overflow due to unhandled wraparound

2024-12-09T09:31:57+00:00

[ Upstream commit caf02626b2bf164a02c808240f19dbf97aced664 ] alloc_buffer() allocates and initializes (with random data) a buffer of requested size. The initialization starts from the beginning of the allocated buffer and incrementally assigns sizeof(uint64_t) random data to each cache line. The initialization uses the size of the buffer to control the initialization flow, decrementing the amount of buffer needing to be initialized after each iteration. The size of the buffer is stored in an unsigned (size_t) variable s64 and the test "s64 > 0" is used to decide if initialization is complete. The problem is that decrementing the buffer size may wrap around if the buffer size is not divisible by "CL_SIZE / sizeof(uint64_t)" resulting in the "s64 > 0" test being true and memory beyond the buffer "initialized". Use a signed value for the buffer size to support all buffer sizes. Fixes: a2561b12fe39 ("selftests/resctrl: Add built in benchmark") Signed-off-by: Reinette Chatre Reviewed-by: Ilpo Järvinen Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests/resctrl: Refactor fill_buf functions

2024-12-09T09:31:57+00:00

[ Upstream commit 24be05591fb7a2a3edd639092c045298dd57aeea ] There are unnecessary nested calls in fill_buf.c: - run_fill_buf() calls fill_cache() - alloc_buffer() calls malloc_and_init_memory() Simplify the code flow and remove those unnecessary call levels by moving the called code inside the calling function and remove the duplicated error print. Resolve the difference in run_fill_buf() and fill_cache() parameter name into 'buf_size' which is more descriptive than 'span'. Also, while moving the allocation related code, rename 'p' into 'buf' to be consistent in naming the variables. Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan Stable-dep-of: caf02626b2bf ("selftests/resctrl: Fix memory overflow due to unhandled wraparound") Signed-off-by: Sasha Levin

selftests/resctrl: Split fill_buf to allow tests finer-grained control

2024-12-09T09:31:57+00:00

[ Upstream commit f8f669699977db503569465b64dc5220ab21bb41 ] MBM, MBA and CMT test cases call run_fill_buf() that in turn calls fill_cache() to alloc and loop indefinitely around the buffer. This binds buffer allocation and running the benchmark into a single bundle so that a selftest cannot allocate a buffer once and reuse it. CAT test doesn't want to loop around the buffer continuously and after rewrite it needs the ability to allocate the buffer separately. Split buffer allocation out of fill_cache() into alloc_buffer(). This change is part of preparation for the new CAT test that allocates a buffer and does multiple passes over the same buffer (but not in an infinite loop). Co-developed-by: Fenghua Yu Signed-off-by: Fenghua Yu Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan Stable-dep-of: caf02626b2bf ("selftests/resctrl: Fix memory overflow due to unhandled wraparound") Signed-off-by: Sasha Levin

selftests/resctrl: Fix closing IMC fds on error and open-code R+W instead of loops

2024-08-03T06:53:43+00:00

[ Upstream commit c44000b6535dc9806b9128d1aed403862b2adab9 ] The imc perf fd close() calls are missing from all error paths. In addition, get_mem_bw_imc() handles fds in a for loop but close() is based on two fixed indexes READ and WRITE. Open code inner for loops to READ+WRITE entries for clarity and add a function to close() IMC fds properly in all cases. Fixes: 7f4d257e3a2a ("selftests/resctrl: Add callback to start a benchmark") Suggested-by: Reinette Chatre Signed-off-by: Ilpo Järvinen Tested-by: Babu Moger Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests/resctrl: Convert perror() to ksft_perror() or ksft_print_msg()

2024-08-03T06:53:43+00:00

[ Upstream commit cc8ff7f5c85c076297b18fb9f6d45ec5569d3d44 ] The resctrl selftest code contains a number of perror() calls. Some of them come with hash character and some don't. The kselftest framework provides ksft_perror() that is compatible with test output formatting so it should be used instead of adding custom hash signs. Some perror() calls are too far away from anything that sets error. For those call sites, ksft_print_msg() must be used instead. Convert perror() to ksft_perror() or ksft_print_msg(). Other related changes: - Remove hash signs - Remove trailing stops & newlines from ksft_perror() - Add terminating newlines for converted ksft_print_msg() - Use consistent capitalization - Small fixes/tweaks to typos & grammar of the messages - Extract error printing out of PARENT_EXIT() to be able to differentiate Signed-off-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan Stable-dep-of: c44000b6535d ("selftests/resctrl: Fix closing IMC fds on error and open-code R+W instead of loops") Signed-off-by: Sasha Levin

selftests/resctrl: Move run_benchmark() to a more fitting file

2024-08-03T06:53:43+00:00

[ Upstream commit 508934b5d15ab79fd5895cc2a6063bc9d95f6a55 ] resctrlfs.c contains mostly functions that interact in some way with resctrl FS entries while functions inside resctrl_val.c deal with measurements and benchmarking. run_benchmark() is located in resctrlfs.c even though it's purpose is not interacting with the resctrl FS but to execute cache checking logic. Move run_benchmark() to resctrl_val.c just before resctrl_val() that makes use of run_benchmark(). Make run_benchmark() static since it's not used between multiple files anymore. Remove return comment from kernel-doc since the function is type void. Signed-off-by: Maciej Wieczor-Retman Reviewed-by: Ilpo Järvinen Reviewed-by: Reinette Chatre Signed-off-by: Shuah Khan Stable-dep-of: c44000b6535d ("selftests/resctrl: Fix closing IMC fds on error and open-code R+W instead of loops") Signed-off-by: Sasha Levin

selftests/resctrl: fix clang build failure: use LOCAL_HDRS

2024-06-12T09:11:49+00:00

[ Upstream commit d8171aa4ca72f1a67bf3c14c59441d63c1d2585f ] First of all, in order to build with clang at all, one must first apply Valentin Obst's build fix for LLVM [1]. Once that is done, then when building with clang, via: make LLVM=1 -C tools/testing/selftests ...the following error occurs: clang: error: cannot specify -o when generating multiple output files This is because clang, unlike gcc, won't accept invocations of this form: clang file1.c header2.h Fix this by using selftests/lib.mk facilities for tracking local header file dependencies: add them to LOCAL_HDRS, leaving only the .c files to be passed to the compiler. [1] https://lore.kernel.org/all/20240329-selftests-libmk-llvm-rfc-v1-1-2f9ed7d1c49f@valentinobst.de/ Fixes: 8e289f454289 ("selftests/resctrl: Add resctrl.h into build deps") Cc: Ilpo Järvinen Signed-off-by: John Hubbard Acked-by: Reinette Chatre Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin

selftests/resctrl: Extend signal handler coverage to unmount on receiving signal

2023-11-28T17:20:08+00:00

[ Upstream commit 3aff5146445582454c35900f3c0c972987cdd595 ] Unmounting resctrl FS has been moved into the per test functions in resctrl_tests.c by commit caddc0fbe495 ("selftests/resctrl: Move resctrl FS mount/umount to higher level"). In case a signal (SIGINT, SIGTERM, or SIGHUP) is received, the running selftest is aborted by ctrlc_handler() which then unmounts resctrl fs before exiting. The current section between signal_handler_register() and signal_handler_unregister(), however, does not cover the entire duration when resctrl FS is mounted. Move signal_handler_register() and signal_handler_unregister() calls from per test files into resctrl_tests.c to properly unmount resctrl fs. In order to not add signal_handler_register()/unregister() n times, create helpers test_prepare() and test_cleanup(). Do not call ksft_exit_fail_msg() in test_prepare() but only in the per test function to keep the control flow cleaner without adding calls to exit() deep into the call chain. Adjust child process kill() call in ctrlc_handler() to only be invoked if the child was already forked. Fixes: caddc0fbe495 ("selftests/resctrl: Move resctrl FS mount/umount to higher level") Signed-off-by: Ilpo Järvinen Tested-by: Shaopeng Tan Reviewed-by: Shaopeng Tan Reviewed-by: Reinette Chatre Cc: Signed-off-by: Shuah Khan Signed-off-by: Sasha Levin