https://github.com/torvalds/linux
Revision c012268b37db6b10b59dac9b7f45956cb9a8bcb2 authored by Michael Ellerman on 05 August 2016, 21:25:53 UTC, committed by Greg Kroah-Hartman on 31 August 2016, 11:12:38 UTC
lkdtm_rodata_do_nothing() is an empty function which is generated in order to test the non-executability of rodata. Currently if function tracing is enabled then an mcount callsite will be generated for lkdtm_rodata_do_nothing(), and it will appear in the list of available functions for function tracing (available_filter_functions). Given it's purpose purely as a test function, it seems preferable for lkdtm_rodata_do_nothing() to be marked notrace, so it doesn't appear as traceable. This also avoids triggering a linker bug on powerpc: https://sourceware.org/bugzilla/show_bug.cgi?id=20428 When the linker sees code that needs to generate a call stub, eg. a branch to mcount(), it assumes the section is executable and dereferences a NULL pointer leading to a linker segfault. Marking lkdtm_rodata_do_nothing() notrace avoids triggering the bug because the function contains no other function calls. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 parent 8c57cac
Tip revision: c012268b37db6b10b59dac9b7f45956cb9a8bcb2 authored by Michael Ellerman on 05 August 2016, 21:25:53 UTC
lkdtm: Mark lkdtm_rodata_do_nothing() notrace
lkdtm: Mark lkdtm_rodata_do_nothing() notrace
Tip revision: c012268
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| .cocciconfig | -rw-r--r-- | 59 bytes |
| .get_maintainer.ignore | -rw-r--r-- | 31 bytes |
| .gitignore | -rw-r--r-- | 1.3 KB |
| .mailmap | -rw-r--r-- | 7.1 KB |
| COPYING | -rw-r--r-- | 18.3 KB |
| CREDITS | -rw-r--r-- | 95.5 KB |
| Kbuild | -rw-r--r-- | 2.8 KB |
| Kconfig | -rw-r--r-- | 252 bytes |
| MAINTAINERS | -rw-r--r-- | 362.7 KB |
| Makefile | -rw-r--r-- | 56.8 KB |
| README | -rw-r--r-- | 18.1 KB |
| REPORTING-BUGS | -rw-r--r-- | 7.3 KB |
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