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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 1B76010000C X-Stat-Signature: grgfcig61ef675rnxgskdqpkuci5jbbb X-HE-Tag: 1718295677-639342 X-HE-Meta: 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 A32gIEY3 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, 13 Jun 2024 17:34:03 +0200 Ilya Leoshkevich wrote: > 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/ > > Reviewed-by: Alexander Potapenko > Signed-off-by: Ilya Leoshkevich > --- Acked-by: Steven Rostedt (Google) -- Steve > kernel/trace/ftrace.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index 65208d3b5ed9..c35ad4362d71 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -7407,6 +7407,7 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, > 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