Daniel Borkmann aa7145c16d bpf, events: fix offset in skb copy handler ... This patch fixes the __output_custom() routine we currently use with bpf_skb_copy(). I missed that when len is larger than the size of the current handle, we can issue multiple invocations of copy_func, and __output_custom() advances destination but also source buffer by the written amount of bytes. When we have __output_custom(), this is actually wrong since in that case the source buffer points to a non-linear object, in our case an skb, which the copy_func helper is supposed to walk. Therefore, since this is non-linear we thus need to pass the offset into the helper, so that copy_func can use it for extracting the data from the source object. Therefore, adjust the callback signatures properly and pass offset into the skb_header_pointer() invoked from bpf_skb_copy() callback. The __DEFINE_OUTPUT_COPY_BODY() is adjusted to accommodate for two things: i) to pass in whether we should advance source buffer or not; this is a compile-time constant condition, ii) to pass in the offset for __output_custom(), which we do with help of __VA_ARGS__, so everything can stay inlined as is currently. Both changes allow for adapting the __output_* fast-path helpers w/o extra overhead. Fixes: 555c8a8623 ("bpf: avoid stack copy and use skb ctx for event output") Fixes: 7e3f977edd ("perf, events: add non-linear data support for raw records") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>		2016-07-25 10:34:11 -07:00
..
callchain.c	perf core: Separate accounting of contexts and real addresses in a stack trace	2016-05-16 23:11:53 -03:00
core.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2016-07-24 00:53:32 -04:00
hw_breakpoint.c	perf: Collapse and fix event_function_call() users	2016-01-21 18:54:24 +01:00
internal.h	bpf, events: fix offset in skb copy handler	2016-07-25 10:34:11 -07:00
Makefile	ftrace: allow architectures to specify ftrace compile options	2015-01-29 09:19:19 +01:00
ring_buffer.c	perf/core: Disable the event on a truncated AUX record	2016-05-12 14:46:11 +02:00
uprobes.c	uprobes: wait for mmap_sem for write killable	2016-05-23 17:04:14 -07:00