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perf bpf augmented_raw_syscalls: Add an assert to make sure sizeof(augmented_arg->value) is a power of two.

Similar to what was done in the previous cset for sizeof(saddr), we need
to make sure sizeof(augmented_arg->value) is a power of two to do bounds
checking using &=:

  augmented_len &= sizeof(augmented_arg->value) - 1;

Suggested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZONrPo0NSqdbXiGx@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2023-08-21 10:40:09 -03:00
parent 262b54b6c9
commit 7d9642311b

View File

@ -160,6 +160,7 @@ unsigned int augmented_arg__read_str(struct augmented_arg *augmented_arg, const
*/
if (string_len > 0) {
augmented_len -= sizeof(augmented_arg->value) - string_len;
_Static_assert(is_power_of_2(sizeof(augmented_arg->value)), "sizeof(augmented_arg->value) needs to be a power of two");
augmented_len &= sizeof(augmented_arg->value) - 1;
augmented_arg->size = string_len;
} else {