From d081a6e353168f15e63eb9e9334757f20343319f Mon Sep 17 00:00:00 2001
From: Daniel Thompson <daniel.thompson@linaro.org>
Date: Wed, 9 Sep 2020 15:17:08 +0100
Subject: [PATCH] kdb: Fix pager search for multi-line strings
Git-commit: d081a6e353168f15e63eb9e9334757f20343319f
Patch-mainline: v5.10-rc1
References: git-fixes
Currently using forward search doesn't handle multi-line strings correctly.
The search routine replaces line breaks with \0 during the search and, for
regular searches ("help | grep Common\n"), there is code after the line
has been discarded or printed to replace the break character.
However during a pager search ("help\n" followed by "/Common\n") when the
string is matched we will immediately return to normal output and the code
that should restore the \n becomes unreachable. Fix this by restoring the
replaced character when we disable the search mode and update the comment
accordingly.
Fixes: fb6daa7520f9d ("kdb: Provide forward search at more prompt")
Link: https://lore.kernel.org/r/20200909141708.338273-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
kernel/debug/kdb/kdb_io.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index e7835ca88e16..6735ac36b718 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -706,12 +706,16 @@ int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap)
size_avail = sizeof(kdb_buffer) - len;
goto kdb_print_out;
}
- if (kdb_grepping_flag >= KDB_GREPPING_FLAG_SEARCH)
+ if (kdb_grepping_flag >= KDB_GREPPING_FLAG_SEARCH) {
/*
* This was a interactive search (using '/' at more
- * prompt) and it has completed. Clear the flag.
+ * prompt) and it has completed. Replace the \0 with
+ * its original value to ensure multi-line strings
+ * are handled properly, and return to normal mode.
*/
+ *cphold = replaced_byte;
kdb_grepping_flag = 0;
+ }
/*
* at this point the string is a full line and
* should be printed, up to the null.
--
2.26.2