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| author | Ilya Leoshkevich <iii@linux.ibm.com> | 2024-06-21 13:34:45 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-07-04 04:30:21 +0200 |
| commit | c02525a33969000fa7b595b743deb4d79804916b (patch) | |
| tree | dfe55738b3be7a277096117c9398376e7acb2b4c | |
| parent | Docs/mm/damon/maintainer-profile: document DAMON community meetups (diff) | |
| download | linux-c02525a33969000fa7b595b743deb4d79804916b.tar.xz linux-c02525a33969000fa7b595b743deb4d79804916b.zip | |
ftrace: unpoison ftrace_regs in ftrace_ops_list_func()
Patch series "kmsan: Enable on s390", v7.
Architectures use assembly code to initialize ftrace_regs and call
ftrace_ops_list_func(). Therefore, from the KMSAN's point of view,
ftrace_regs is poisoned on ftrace_ops_list_func entry(). This causes
KMSAN warnings when running the ftrace testsuite.
Fix by trusting the architecture-specific assembly code and always
unpoisoning ftrace_regs in ftrace_ops_list_func.
The issue was not encountered on x86_64 so far only by accident:
assembly-allocated ftrace_regs was overlapping a stale partially
unpoisoned stack frame. Poisoning stack frames before returns [1] makes
the issue appear on x86_64 as well.
[1] https://github.com/iii-i/llvm-project/commits/msan-poison-allocas-before-returning-2024-06-12/
Link: https://lkml.kernel.org/r/20240621113706.315500-1-iii@linux.ibm.com
Link: https://lkml.kernel.org/r/20240621113706.315500-2-iii@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <kasan-dev@googlegroups.com>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | kernel/trace/ftrace.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index eacab4020508..f1150f081d6b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7404,6 +7404,7 @@ out: void arch_ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { + kmsan_unpoison_memory(fregs, sizeof(*fregs)); __ftrace_ops_list_func(ip, parent_ip, NULL, fregs); } #else |