On Sat, Jan 25, 2025 at 12:30 AM Levi Zim via B4 Relay devnull+rsworktech.outlook.com@kernel.org wrote:
From: Levi Zim rsworktech@outlook.com
This update brings the new bpf_probe_read_{kernel,user} helpers
Signed-off-by: Levi Zim rsworktech@outlook.com
tools/include/uapi/linux/bpf.h | 49 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 2acf9b33637174bd16b1d12ccc6410c5f55a7ea9..f92cf809b50bc393d54eb0e8de2e1ce2a39e95d0 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5805,6 +5805,52 @@ union bpf_attr {
0 on success.**-ENOENT** if the bpf_local_storage cannot be found.
- long bpf_probe_read_kernel_dynptr(const struct bpf_dynptr *dst, u32 offset, u32 size, const void *unsafe_ptr, u64 flags)
Description
Safely attempt to read *size* bytes from kernel space address
*unsafe_ptr* and store the data in *dst* starting from *offset*.
*flags* is currently unused.
Return
0 on success.
**-E2BIG** if *offset* + *len* exceeds the length of *src*'s data
**-EINVAL** if *src* is an invalid dynptr or doesn't support this
support this helper, or if *flags* is not 0.
Or other negative errors on failure reading kernel memory.
- long bpf_probe_read_user_dynptr(const struct bpf_dynptr *dst, u32 offset, u32 size, const void *unsafe_ptr, u64 flags)
Description
Safely attempt to read *size* bytes from user space address
*unsafe_ptr* and store the data in *dst* starting from *offset*.
*flags* is currently unused.
Return
0 on success.
**-E2BIG** if *offset* + *len* exceeds the length of *src*'s data
**-EINVAL** if *src* is an invalid dynptr or doesn't support this
support this helper, or if *flags* is not 0.
Or other negative errors on failure reading user space memory.
- long bpf_copy_from_user_dynptr(const struct bpf_dynptr *dst, u32 offset, u32 size, const void *user_ptr, u64 flags)
Description
Read *size* bytes from user space address *user_ptr* and store
the data in *dst* starting from *offset*.
This is a wrapper of **copy_from_user**\ ().
*flags* is currently unused.
Return
0 on success.
**-E2BIG** if *offset* + *len* exceeds the length of *src*'s data
**-EINVAL** if *src* is an invalid dynptr or doesn't support this
support this helper, or if *flags* is not 0.
*/
Or other negative errors on failure reading user space memory.#define ___BPF_FUNC_MAPPER(FN, ctx...) \ FN(unspec, 0, ##ctx) \ @@ -6019,6 +6065,9 @@ union bpf_attr { FN(user_ringbuf_drain, 209, ##ctx) \ FN(cgrp_storage_get, 210, ##ctx) \ FN(cgrp_storage_delete, 211, ##ctx) \
we probably want to add some big and very noticeable comment here suggesting kfunc route, to save people time next time. Please consider adding it as a separate patch for v2.
FN(probe_read_kernel_dynptr, 212, ##ctx) \FN(probe_read_user_dynptr, 213, ##ctx) \FN(copy_from_user_dynptr, 214, ##ctx) \ /* *//* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't
-- 2.48.1