| Message ID | 20230517034510.15639-2-zegao@tencent.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Make fprobe + rethook immune to recursion | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
Hi Ze Gao, On Wed, 17 May 2023 11:45:06 +0800 Ze Gao <zegao2021@gmail.com> wrote: > This patch replaces preempt_{disable, enable} with its corresponding > notrace version in rethook_trampoline_handler so no worries about stack > recursion or overflow introduced by preempt_count_{add, sub} under > fprobe + rethook context. > > Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook") > Signed-off-by: Ze Gao <zegao@tencent.com> > Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > Cc: <stable@vger.kernel.org> > Link: https://lore.kernel.org/linux-trace-kernel/20230516071830.8190-2-zegao@tencent.com Note that you don't need to add Link tag of the previous version for each patch. I'll add it when I pick it :) Thank you, > --- > kernel/trace/rethook.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c > index 32c3dfdb4d6a..60f6cb2b486b 100644 > --- a/kernel/trace/rethook.c > +++ b/kernel/trace/rethook.c > @@ -288,7 +288,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, > * These loops must be protected from rethook_free_rcu() because those > * are accessing 'rhn->rethook'. > */ > - preempt_disable(); > + preempt_disable_notrace(); > > /* > * Run the handler on the shadow stack. Do not unlink the list here because > @@ -321,7 +321,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, > first = first->next; > rethook_recycle(rhn); > } > - preempt_enable(); > + preempt_enable_notrace(); > > return correct_ret_addr; > } > -- > 2.40.1 >
Great, thanks! Regards, Ze On Wed, May 17, 2023 at 7:59 PM Masami Hiramatsu <mhiramat@kernel.org> wrote: > > Hi Ze Gao, > > On Wed, 17 May 2023 11:45:06 +0800 > Ze Gao <zegao2021@gmail.com> wrote: > > > This patch replaces preempt_{disable, enable} with its corresponding > > notrace version in rethook_trampoline_handler so no worries about stack > > recursion or overflow introduced by preempt_count_{add, sub} under > > fprobe + rethook context. > > > > Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook") > > Signed-off-by: Ze Gao <zegao@tencent.com> > > Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > Cc: <stable@vger.kernel.org> > > Link: https://lore.kernel.org/linux-trace-kernel/20230516071830.8190-2-zegao@tencent.com > > Note that you don't need to add Link tag of the previous version for each patch. > I'll add it when I pick it :) > > Thank you, > > > --- > > kernel/trace/rethook.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c > > index 32c3dfdb4d6a..60f6cb2b486b 100644 > > --- a/kernel/trace/rethook.c > > +++ b/kernel/trace/rethook.c > > @@ -288,7 +288,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, > > * These loops must be protected from rethook_free_rcu() because those > > * are accessing 'rhn->rethook'. > > */ > > - preempt_disable(); > > + preempt_disable_notrace(); > > > > /* > > * Run the handler on the shadow stack. Do not unlink the list here because > > @@ -321,7 +321,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, > > first = first->next; > > rethook_recycle(rhn); > > } > > - preempt_enable(); > > + preempt_enable_notrace(); > > > > return correct_ret_addr; > > } > > -- > > 2.40.1 > > > > > -- > Masami Hiramatsu (Google) <mhiramat@kernel.org>
diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c index 32c3dfdb4d6a..60f6cb2b486b 100644 --- a/kernel/trace/rethook.c +++ b/kernel/trace/rethook.c @@ -288,7 +288,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, * These loops must be protected from rethook_free_rcu() because those * are accessing 'rhn->rethook'. */ - preempt_disable(); + preempt_disable_notrace(); /* * Run the handler on the shadow stack. Do not unlink the list here because @@ -321,7 +321,7 @@ unsigned long rethook_trampoline_handler(struct pt_regs *regs, first = first->next; rethook_recycle(rhn); } - preempt_enable(); + preempt_enable_notrace(); return correct_ret_addr; }
This patch replaces preempt_{disable, enable} with its corresponding notrace version in rethook_trampoline_handler so no worries about stack recursion or overflow introduced by preempt_count_{add, sub} under fprobe + rethook context. Fixes: 54ecbe6f1ed5 ("rethook: Add a generic return hook") Signed-off-by: Ze Gao <zegao@tencent.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/linux-trace-kernel/20230516071830.8190-2-zegao@tencent.com --- kernel/trace/rethook.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)