On Mar 30, 2021, at 7:22 AM, Pedro Tammela pctammela@gmail.com wrote:
Em seg., 29 de mar. de 2021 às 13:10, Song Liu songliubraving@fb.com escreveu:
On Mar 28, 2021, at 9:10 AM, Pedro Tammela pctammela@gmail.com wrote:
The current code only checks flags in 'bpf_ringbuf_output()'.
Signed-off-by: Pedro Tammela pctammela@mojatatu.com
include/uapi/linux/bpf.h | 8 ++++---- kernel/bpf/ringbuf.c | 13 +++++++++++-- tools/include/uapi/linux/bpf.h | 8 ++++---- 3 files changed, 19 insertions(+), 10 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 100cb2e4c104..232b5e5dd045 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -4073,7 +4073,7 @@ union bpf_attr {
Valid pointer with *size* bytes of memory available; NULL,otherwise.
- void bpf_ringbuf_submit(void *data, u64 flags)
- int bpf_ringbuf_submit(void *data, u64 flags)
This should be "long" instead of "int".
- Description
Submit reserved ring buffer sample, pointed to by *data*.If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification@@ -4083,9 +4083,9 @@ union bpf_attr {
If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notificationof new data availability is sent unconditionally.- Return
Nothing. Always succeeds.
0 on success, or a negative error in case of failure.
- void bpf_ringbuf_discard(void *data, u64 flags)
- int bpf_ringbuf_discard(void *data, u64 flags)
Ditto. And same for tools/include/uapi/linux/bpf.h
- Description
Discard reserved ring buffer sample, pointed to by *data*.If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification@@ -4095,7 +4095,7 @@ union bpf_attr {
If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notificationof new data availability is sent unconditionally.- Return
Nothing. Always succeeds.
0 on success, or a negative error in case of failure.
- u64 bpf_ringbuf_query(void *ringbuf, u64 flags)
- Description
diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c index f25b719ac786..f76dafe2427e 100644 --- a/kernel/bpf/ringbuf.c +++ b/kernel/bpf/ringbuf.c @@ -397,26 +397,35 @@ static void bpf_ringbuf_commit(void *sample, u64 flags, bool discard)
BPF_CALL_2(bpf_ringbuf_submit, void *, sample, u64, flags) {
if (unlikely(flags & ~(BPF_RB_NO_WAKEUP | BPF_RB_FORCE_WAKEUP)))return -EINVAL;We can move this check to bpf_ringbuf_commit().
I don't believe we can because in 'bpf_ringbuf_output()' the flag checking in 'bpf_ringbuf_commit()' is already too late.
I see. Let's keep it in current functions then.
Thanks, Song