kallsyms: fix segfault in prefix_underscores_count()
Commit b478b782e110fdb4135caa3062b6d687e989d994 "kallsyms, tracing: output
more proper symbol name" introduces a "bugfix" that introduces a segfault
in kallsyms in my configurations.
The cause is the introduction of prefix_underscores_count() which attempts
to count underscores, even in symbols that do not have them. As a result,
it just uselessly runs past the end of the buffer until it crashes:
CC init/version.o
LD init/built-in.o
LD .tmp_vmlinux1
KSYM .tmp_kallsyms1.S
/bin/sh: line 1: 16934 Done sh-linux-gnu-nm -n .tmp_vmlinux1
16935 Segmentation fault | scripts/kallsyms > .tmp_kallsyms1.S
make: *** [.tmp_kallsyms1.S] Error 139
This simplifies the logic and just does a straightforward count.
Signed-off-by: Paul Mundt <[email protected]>
Reviewed-by: Li Zefan <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Cc: Paulo Marques <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: <[email protected]> [2.6.30.x, 2.6.31.x]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index 64343cc..86c3896 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -585,7 +585,7 @@
{
const char *tail = str;
- while (*tail != '_')
+ while (*tail == '_')
tail++;
return tail - str;
