From: Mykyta Yatsenko <yatsenko@xxxxxxxx>
This patch adds new kfuncs that enable reading variable-length
user or kernel data directly into dynptrs.
These kfuncs provide a way to perform dynamically-sized reads
while maintaining memory safety. Unlike existing
`bpf_probe_read_{user|kernel}` APIs, which are limited to constant-sized
reads, these new kfuncs allow for more flexible data access.
v4 -> v5
* Fix pointers annotations, use __user where necessary, cast where needed
v3 -> v4
* Added pid filtering in selftests
v2 -> v3
* Add KF_TRUSTED_ARGS for kfuncs that take pointer to task_struct
as an argument
* Remove checks for non-NULL task, where it was not necessary
* Added comments on constants used in selftests, etc.
v1 -> v2
* Renaming helper functions to use "user_str" instead of "user_data_str"
suffix
Mykyta Yatsenko (3):
helpers: make few bpf helpers public
bpf: implement dynptr copy kfuncs
selftests/bpf: introduce tests for dynptr copy kfuncs
include/linux/bpf.h | 14 ++
kernel/bpf/helpers.c | 22 +-
kernel/trace/bpf_trace.c | 193 +++++++++++++++
tools/testing/selftests/bpf/DENYLIST | 1 +
.../testing/selftests/bpf/prog_tests/dynptr.c | 13 +
.../selftests/bpf/progs/dynptr_success.c | 230 ++++++++++++++++++
6 files changed, 461 insertions(+), 12 deletions(-)
--
2.49.0
