Merge branch 'BPF iterator for UNIX domain socket.'

Kuniyuki Iwashima says:

====================

This patch set adds BPF iterator support for UNIX domain socket.  The first
patch implements it, and the second adds "%c" support for BPF_SEQ_PRINTF().

Thanks to Yonghong Song for the fix [0] for the LLVM code gen.  The fix
prevents the LLVM compiler from transforming the loop exit condition '<' to
'!=', where the upper bound is not a constant.  The transformation leads
the verifier to interpret it as an infinite loop.

And thanks to Andrii Nakryiko for its workaround [1].

[0] https://reviews.llvm.org/D107483
[1] https://lore.kernel.org/netdev/CAEf4BzZ3sVx1m1mOCcPcuVPiY6cWEAO=6VGHDiXEs9ZVD-RoLg@mail.gmail.com/

Changelog:
  v6:
  - Align the header "Inde" column
  - Change int vars to __u64 not to break test_progs-no_alu32
  - Move the if statement into the for loop not to depend on the fix [0]
  - Drop the README change
  - Modify "%c" positive test patterns

  v5:
  https://lore.kernel.org/netdev/20210812164557.79046-1-kuniyu@amazon.co.jp/
  - Align header line of bpf_iter_unix.c
  - Add test for "%c"

  v4:
  https://lore.kernel.org/netdev/20210810092807.13190-1-kuniyu@amazon.co.jp/
  - Check IS_BUILTIN(CONFIG_UNIX)
  - Support "%c" in BPF_SEQ_PRINTF()
  - Uncomment the code to print the name of the abstract socket
  - Mention the LLVM fix in README.rst
  - Remove the 'aligned' attribute in bpf_iter.h
  - Keep the format string on a single line

  v3:
  https://lore.kernel.org/netdev/20210804070851.97834-1-kuniyu@amazon.co.jp/
  - Export some functions for CONFIG_UNIX=m

  v2:
  https://lore.kernel.org/netdev/20210803011110.21205-1-kuniyu@amazon.co.jp/
  - Implement bpf_iter specific seq_ops->stop()
  - Add bpf_iter__unix in bpf_iter.h
  - Move common definitions in selftest to bpf_tracing_net.h
  - Include the code for abstract UNIX domain socket as comment in selftest
  - Use ASSERT_OK_PTR() instead of CHECK()
  - Make ternary operators on single line

  v1:
  https://lore.kernel.org/netdev/20210729233645.4869-1-kuniyu@amazon.co.jp/
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/tools/testing/selftests/bpf/progs/test_snprintf.c b/tools/testing/selftests/bpf/progs/test_snprintf.c
index e2ad26150f9b..8fda07544023 100644
--- a/tools/testing/selftests/bpf/progs/test_snprintf.c
+++ b/tools/testing/selftests/bpf/progs/test_snprintf.c
@@ -59,9 +59,9 @@ int handler(const void *ctx)
 	/* Kernel pointers */
 	addr_ret = BPF_SNPRINTF(addr_out, sizeof(addr_out), "%pK %px %p",
 				0, 0xFFFF00000ADD4E55, 0xFFFF00000ADD4E55);
-	/* Strings embedding */
-	str_ret  = BPF_SNPRINTF(str_out, sizeof(str_out), "%s %+05s",
-				str1, longstr);
+	/* Strings and single-byte character embedding */
+	str_ret  = BPF_SNPRINTF(str_out, sizeof(str_out), "%s % 9c %+2c %-3c %04c %0c %+05s",
+				str1, 'a', 'b', 'c', 'd', 'e', longstr);
 	/* Overflow */
 	over_ret = BPF_SNPRINTF(over_out, sizeof(over_out), "%%overflow");
 	/* Padding of fixed width numbers */