From nobody Mon Nov 25 00:20:18 2024 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0FF4819D88D; Thu, 31 Oct 2024 15:22:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=167.114.26.122 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730388160; cv=none; b=I7W5QJg3jMPNniVmcNIrp6ZMoLbvAhdgSWuYOASc9qp27nSTXC7wnbP2LbpAD1zfl3qrlnAz+pgBWzkxIh+0pTAcMfJMmEI8k2xxKoQLWGcIc2jOJVfUaG8FgCe7KWtIhzsdrt5MwB5lpoBe49jPBNNRKexHXmKajrXm3dqajKA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730388160; c=relaxed/simple; bh=8naxjRh54yOwprdFdMeqgDqAH4UaeTJCrDg/IGHwGN0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Unhov3oL6ZRPzjqLy+KCKYBxzfV7GAW3J8vjMKXo4FonguNbfzYNCe0c7xL7SGTuN/diH3mXRJN4Lsi5zi/cUDUrbgIq8/nPEFUMd2m5XTZBxPac56DeLnIgLG+ZhVTzdZoemif5HoJ2zqQ6F0XTzGPSLDsqpb+Kfc2O4dcmOUE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=FEgOVD4I; arc=none smtp.client-ip=167.114.26.122 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="FEgOVD4I" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1730388157; bh=8naxjRh54yOwprdFdMeqgDqAH4UaeTJCrDg/IGHwGN0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FEgOVD4IxljO0igYKYLWVQl0e1OAvF7JNzYa8qBR6YuvPO2YCxmc3gccru1Wg+1Wg 4pZYreX7icrJ+928CEa1lPuC36+b3/f3/QYGyjM/5dfbn4Wi+4GCiWMWepmmotJlYu 8BRDz4jIwx/mGBNglS75S3VsUwejPENx70TJaau4UrFs38ul3UW8CjUKOSXCSYCjuW ljYpqz9QHCfCnEMJppQzxItZR9lu+Q/YbzIZreQo32KXuM+oGX67yDZa4BVK7LfzpI e9BPjoRu4Veg1c2Eq6TanRT9Ilz2k+w7lF644+Vw3BP+z5CubSixl7b2s8K/rp8wRs h+TwiudHEt4zw== Received: from thinkos.internal.efficios.com (96-127-217-162.qc.cable.ebox.net [96.127.217.162]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4XfSRJ5FxpzYqS; Thu, 31 Oct 2024 11:22:36 -0400 (EDT) From: Mathieu Desnoyers To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Thomas Gleixner , Michael Jeanson , Masami Hiramatsu , Peter Zijlstra , Alexei Starovoitov , Yonghong Song , "Paul E . McKenney" , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Namhyung Kim , Andrii Nakryiko , bpf@vger.kernel.org, Joel Fernandes , Jordan Rife , linux-trace-kernel@vger.kernel.org Subject: [PATCH v5 resend 1/4] tracing: Introduce tracepoint extended structure Date: Thu, 31 Oct 2024 11:20:53 -0400 Message-Id: <20241031152056.744137-2-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> References: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Shrink the struct tracepoint size from 80 bytes to 72 bytes on x86-64 by moving the (typically NULL) regfunc/unregfunc pointers to an extended structure. Tested-by: Jordan Rife Signed-off-by: Mathieu Desnoyers Cc: Michael Jeanson Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Alexei Starovoitov Cc: Yonghong Song Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Andrii Nakryiko Cc: bpf@vger.kernel.org Cc: Joel Fernandes Cc: Jordan Rife Cc: linux-trace-kernel@vger.kernel.org --- Changes since v4: - Add static to DEFINE_TRACE_FN. --- include/linux/tracepoint-defs.h | 8 ++++++-- include/linux/tracepoint.h | 19 +++++++++++++------ kernel/tracepoint.c | 9 ++++----- 3 files changed, 23 insertions(+), 13 deletions(-) diff --git a/include/linux/tracepoint-defs.h b/include/linux/tracepoint-def= s.h index 60a6e8314d4c..967c08d9da84 100644 --- a/include/linux/tracepoint-defs.h +++ b/include/linux/tracepoint-defs.h @@ -29,6 +29,11 @@ struct tracepoint_func { int prio; }; =20 +struct tracepoint_ext { + int (*regfunc)(void); + void (*unregfunc)(void); +}; + struct tracepoint { const char *name; /* Tracepoint name */ struct static_key_false key; @@ -36,9 +41,8 @@ struct tracepoint { void *static_call_tramp; void *iterator; void *probestub; - int (*regfunc)(void); - void (*unregfunc)(void); struct tracepoint_func __rcu *funcs; + struct tracepoint_ext *ext; }; =20 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 0dc67fad706c..862ab49177a4 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -302,7 +302,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(t= racepoint_ptr_t *p) * structures, so we create an array of pointers that will be used for ite= ration * on the tracepoints. */ -#define DEFINE_TRACE_FN(_name, _reg, _unreg, proto, args) \ +#define __DEFINE_TRACE_EXT(_name, _ext, proto, args) \ static const char __tpstrtab_##_name[] \ __section("__tracepoints_strings") =3D #_name; \ extern struct static_call_key STATIC_CALL_KEY(tp_func_##_name); \ @@ -316,9 +316,9 @@ static inline struct tracepoint *tracepoint_ptr_deref(t= racepoint_ptr_t *p) .static_call_tramp =3D STATIC_CALL_TRAMP_ADDR(tp_func_##_name), \ .iterator =3D &__traceiter_##_name, \ .probestub =3D &__probestub_##_name, \ - .regfunc =3D _reg, \ - .unregfunc =3D _unreg, \ - .funcs =3D NULL }; \ + .funcs =3D NULL, \ + .ext =3D _ext, \ + }; \ __TRACEPOINT_ENTRY(_name); \ int __traceiter_##_name(void *__data, proto) \ { \ @@ -341,8 +341,15 @@ static inline struct tracepoint *tracepoint_ptr_deref(= tracepoint_ptr_t *p) } \ DEFINE_STATIC_CALL(tp_func_##_name, __traceiter_##_name); =20 -#define DEFINE_TRACE(name, proto, args) \ - DEFINE_TRACE_FN(name, NULL, NULL, PARAMS(proto), PARAMS(args)); +#define DEFINE_TRACE_FN(_name, _reg, _unreg, _proto, _args) \ + static struct tracepoint_ext __tracepoint_ext_##_name =3D { \ + .regfunc =3D _reg, \ + .unregfunc =3D _unreg, \ + }; \ + __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARA= MS(_args)); + +#define DEFINE_TRACE(_name, _proto, _args) \ + __DEFINE_TRACE_EXT(_name, NULL, PARAMS(_proto), PARAMS(_args)); =20 #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \ EXPORT_SYMBOL_GPL(__tracepoint_##name); \ diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 6474e2cf22c9..5658dc92f5b5 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -278,8 +278,8 @@ static int tracepoint_add_func(struct tracepoint *tp, struct tracepoint_func *old, *tp_funcs; int ret; =20 - if (tp->regfunc && !static_key_enabled(&tp->key)) { - ret =3D tp->regfunc(); + if (tp->ext && tp->ext->regfunc && !static_key_enabled(&tp->key)) { + ret =3D tp->ext->regfunc(); if (ret < 0) return ret; } @@ -362,9 +362,8 @@ static int tracepoint_remove_func(struct tracepoint *tp, switch (nr_func_state(tp_funcs)) { case TP_FUNC_0: /* 1->0 */ /* Removed last function */ - if (tp->unregfunc && static_key_enabled(&tp->key)) - tp->unregfunc(); - + if (tp->ext && tp->ext->unregfunc && static_key_enabled(&tp->key)) + tp->ext->unregfunc(); static_branch_disable(&tp->key); /* Set iterator static call */ tracepoint_update_call(tp, tp_funcs); --=20 2.39.5 From nobody Mon Nov 25 00:20:18 2024 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9600F19E99C; Thu, 31 Oct 2024 15:22:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; 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McKenney" , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Namhyung Kim , Andrii Nakryiko , bpf@vger.kernel.org, Joel Fernandes , Jordan Rife , linux-trace-kernel@vger.kernel.org, Andrii Nakryiko Subject: [PATCH v5 resend 2/4] tracing: Introduce tracepoint_is_faultable() Date: Thu, 31 Oct 2024 11:20:54 -0400 Message-Id: <20241031152056.744137-3-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> References: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Introduce a "faultable" flag within the extended structure to know whether a tracepoint needs rcu tasks trace grace period before reclaim. This can be queried using tracepoint_is_faultable(). Acked-by: Andrii Nakryiko Tested-by: Jordan Rife Signed-off-by: Mathieu Desnoyers Cc: Michael Jeanson Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Alexei Starovoitov Cc: Yonghong Song Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Andrii Nakryiko Cc: bpf@vger.kernel.org Cc: Joel Fernandes Cc: Jordan Rife Cc: linux-trace-kernel@vger.kernel.org --- Changes since v4: - Add static to DEFINE_TRACE_SYSCALL. --- include/linux/tracepoint-defs.h | 2 ++ include/linux/tracepoint.h | 24 ++++++++++++++++++++++++ include/trace/define_trace.h | 2 +- 3 files changed, 27 insertions(+), 1 deletion(-) diff --git a/include/linux/tracepoint-defs.h b/include/linux/tracepoint-def= s.h index 967c08d9da84..aebf0571c736 100644 --- a/include/linux/tracepoint-defs.h +++ b/include/linux/tracepoint-defs.h @@ -32,6 +32,8 @@ struct tracepoint_func { struct tracepoint_ext { int (*regfunc)(void); void (*unregfunc)(void); + /* Flags. */ + unsigned int faultable:1; }; =20 struct tracepoint { diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 862ab49177a4..906f3091d23d 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -104,6 +104,12 @@ void for_each_tracepoint_in_module(struct module *mod, * tracepoint_synchronize_unregister must be called between the last trace= point * probe unregistration and the end of module exit to make sure there is no * caller executing a probe when it is freed. + * + * An alternative is to use the following for batch reclaim associated + * with a given tracepoint: + * + * - tracepoint_is_faultable() =3D=3D false: call_rcu() + * - tracepoint_is_faultable() =3D=3D true: call_rcu_tasks_trace() */ #ifdef CONFIG_TRACEPOINTS static inline void tracepoint_synchronize_unregister(void) @@ -111,9 +117,17 @@ static inline void tracepoint_synchronize_unregister(v= oid) synchronize_rcu_tasks_trace(); synchronize_rcu(); } +static inline bool tracepoint_is_faultable(struct tracepoint *tp) +{ + return tp->ext && tp->ext->faultable; +} #else static inline void tracepoint_synchronize_unregister(void) { } +static inline bool tracepoint_is_faultable(struct tracepoint *tp) +{ + return false; +} #endif =20 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS @@ -345,6 +359,15 @@ static inline struct tracepoint *tracepoint_ptr_deref(= tracepoint_ptr_t *p) static struct tracepoint_ext __tracepoint_ext_##_name =3D { \ .regfunc =3D _reg, \ .unregfunc =3D _unreg, \ + .faultable =3D false, \ + }; \ + __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARA= MS(_args)); + +#define DEFINE_TRACE_SYSCALL(_name, _reg, _unreg, _proto, _args) \ + static struct tracepoint_ext __tracepoint_ext_##_name =3D { \ + .regfunc =3D _reg, \ + .unregfunc =3D _unreg, \ + .faultable =3D true, \ }; \ __DEFINE_TRACE_EXT(_name, &__tracepoint_ext_##_name, PARAMS(_proto), PARA= MS(_args)); =20 @@ -389,6 +412,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(t= racepoint_ptr_t *p) #define __DECLARE_TRACE_SYSCALL __DECLARE_TRACE =20 #define DEFINE_TRACE_FN(name, reg, unreg, proto, args) +#define DEFINE_TRACE_SYSCALL(name, reg, unreg, proto, args) #define DEFINE_TRACE(name, proto, args) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) diff --git a/include/trace/define_trace.h b/include/trace/define_trace.h index ff5fa17a6259..63fea2218afa 100644 --- a/include/trace/define_trace.h +++ b/include/trace/define_trace.h @@ -48,7 +48,7 @@ =20 #undef TRACE_EVENT_SYSCALL #define TRACE_EVENT_SYSCALL(name, proto, args, struct, assign, print, reg,= unreg) \ - DEFINE_TRACE_FN(name, reg, unreg, PARAMS(proto), PARAMS(args)) + DEFINE_TRACE_SYSCALL(name, reg, unreg, PARAMS(proto), PARAMS(args)) =20 #undef TRACE_EVENT_NOP #define TRACE_EVENT_NOP(name, proto, args, struct, assign, print) --=20 2.39.5 From nobody Mon Nov 25 00:20:18 2024 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D72A219EEB4; 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Thu, 31 Oct 2024 11:22:37 -0400 (EDT) From: Mathieu Desnoyers To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Thomas Gleixner , Michael Jeanson , Masami Hiramatsu , Peter Zijlstra , Alexei Starovoitov , Yonghong Song , "Paul E . McKenney" , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Namhyung Kim , Andrii Nakryiko , bpf@vger.kernel.org, Joel Fernandes , Jordan Rife , linux-trace-kernel@vger.kernel.org, syzbot+b390c8062d8387b6272a@syzkaller.appspotmail.com Subject: [PATCH v5 resend 3/4] tracing: Fix syscall tracepoint use-after-free Date: Thu, 31 Oct 2024 11:20:55 -0400 Message-Id: <20241031152056.744137-4-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> References: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The grace period used internally within tracepoint.c:release_probes() uses call_rcu() to batch waiting for quiescence of old probe arrays, rather than using the tracepoint_synchronize_unregister() which blocks while waiting for quiescence. With the introduction of faultable syscall tracepoints, this causes use-after-free issues reproduced with syzkaller. Fix this by using the appropriate call_rcu() or call_rcu_tasks_trace() before invoking the rcu_free_old_probes callback. This can be chosen using the tracepoint_is_faultable() API. A similar issue exists in bpf use of call_rcu(). Fixing this is left to a separate change. Reported-by: syzbot+b390c8062d8387b6272a@syzkaller.appspotmail.com Fixes: a363d27cdbc2 ("tracing: Allow system call tracepoints to handle page= faults") Tested-by: Jordan Rife Signed-off-by: Mathieu Desnoyers Cc: Michael Jeanson Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Alexei Starovoitov Cc: Yonghong Song Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Andrii Nakryiko Cc: bpf@vger.kernel.org Cc: Joel Fernandes Cc: Jordan Rife Cc: linux-trace-kernel@vger.kernel.org --- Changes since v0: - Introduce tracepoint_call_rcu(), - Fix bpf_link_free() use of call_rcu as well. Changes since v1: - Use tracepoint_call_rcu() for bpf_prog_put as well. Changes since v2: - Do not cover bpf changes in the same commit, let bpf developers implement it. Changes since v3: - Use tracepoint_is_faultable(). --- kernel/tracepoint.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 5658dc92f5b5..1848ce7e2976 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -106,13 +106,16 @@ static void rcu_free_old_probes(struct rcu_head *head) kfree(container_of(head, struct tp_probes, rcu)); } =20 -static inline void release_probes(struct tracepoint_func *old) +static inline void release_probes(struct tracepoint *tp, struct tracepoint= _func *old) { if (old) { struct tp_probes *tp_probes =3D container_of(old, struct tp_probes, probes[0]); =20 - call_rcu(&tp_probes->rcu, rcu_free_old_probes); + if (tracepoint_is_faultable(tp)) + call_rcu_tasks_trace(&tp_probes->rcu, rcu_free_old_probes); + else + call_rcu(&tp_probes->rcu, rcu_free_old_probes); } } =20 @@ -334,7 +337,7 @@ static int tracepoint_add_func(struct tracepoint *tp, break; } =20 - release_probes(old); + release_probes(tp, old); return 0; } =20 @@ -405,7 +408,7 @@ static int tracepoint_remove_func(struct tracepoint *tp, WARN_ON_ONCE(1); break; } - release_probes(old); + release_probes(tp, old); return 0; } =20 --=20 2.39.5 From nobody Mon Nov 25 00:20:18 2024 Received: from smtpout.efficios.com (smtpout.efficios.com [167.114.26.122]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 43EEA19EEC0; Thu, 31 Oct 2024 15:22:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=167.114.26.122 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730388161; cv=none; b=cS6sIS8a5xN+iFWls+lq9r2utvyDYwD+ZeNr/vRiLfboO6sU6v/cVckigLR2kEAfYahAqE/OHJAqb4DOJvMG44FsBhgGaPrLd6oaFNjsKI6iVvv4GBoJ43s7oejVATZ5igPZbZ95KD5yUGWLQWKyM1fakI7vvcQ2LZnvwSUCHEQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730388161; c=relaxed/simple; bh=1JG3SedAvu6H20LverMfft7wKhK0l6XRFxFKT0bDtNY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=QxW+Usryr+u43y/MpUY6d67xsJ5KiSWSDHrtTQaEiSGETAdUDP352Tl00YMqwUoF2jy3Zk/ih9HAb8XQVRfrLy+0e2SReYe5+oOb5r0u1p5yCcwJZXH9fR3SEsaDATbV90CQ6Pxr7gQTEvm7EskjrIPeYDk29ckzGgUCIjX31E8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=q7RzlL20; arc=none smtp.client-ip=167.114.26.122 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="q7RzlL20" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=efficios.com; s=smtpout1; t=1730388158; bh=1JG3SedAvu6H20LverMfft7wKhK0l6XRFxFKT0bDtNY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q7RzlL20hK5IMI78YT99IFbNkuxbPnWE61ntFTjEAZ9zUs2WIdTrBSDp03Mlgrm0k 5/LXPja03k1+FSHzGv1YyXAPHZsxdhXi2fWPqR+oRvxjSjBjp45KDHhm5dmS5YgddB RzosnGeIoePA9VPEld3MMAdW9PCNsNwq2EVxAwEQGisow1Sw+HGZkr2H3Ae4x/lq5h lM6/nkavFjVm05w7dSRRPJfIrQOapbmRiO0AM41zPWBWnZ8JoOmyRYMQVshxYT9tEL SjDl8vcvApISIUQ+G0gQVtKqNMtzx+VUjYTHkKdhLiIw1E2TBx7GxX24qbHxdyD/EZ wKIvYXfTNolGA== Received: from thinkos.internal.efficios.com (96-127-217-162.qc.cable.ebox.net [96.127.217.162]) by smtpout.efficios.com (Postfix) with ESMTPSA id 4XfSRL0KgbzYlN; Thu, 31 Oct 2024 11:22:38 -0400 (EDT) From: Mathieu Desnoyers To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Mathieu Desnoyers , Thomas Gleixner , Michael Jeanson , Masami Hiramatsu , Peter Zijlstra , Alexei Starovoitov , Yonghong Song , "Paul E . McKenney" , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Namhyung Kim , Andrii Nakryiko , bpf@vger.kernel.org, Joel Fernandes , Jordan Rife , linux-trace-kernel@vger.kernel.org Subject: [PATCH v5 resend 4/4] tracing: Add might_fault() check in __DECLARE_TRACE_SYSCALL Date: Thu, 31 Oct 2024 11:20:56 -0400 Message-Id: <20241031152056.744137-5-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> References: <20241031152056.744137-1-mathieu.desnoyers@efficios.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Catch incorrect use of syscall tracepoints even if no probes are registered by adding a might_fault() check in trace_##name() emitted by __DECLARE_TRACE_SYSCALL. Suggested-by: Thomas Gleixner Tested-by: Jordan Rife Signed-off-by: Mathieu Desnoyers Cc: Thomas Gleixner Cc: Michael Jeanson Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Alexei Starovoitov Cc: Yonghong Song Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Andrii Nakryiko Cc: bpf@vger.kernel.org Cc: Joel Fernandes Cc: Jordan Rife Cc: linux-trace-kernel@vger.kernel.org --- Changes since v4: - Move might_fault() to trace_##name() emitted by __DECLARE_TRACE_SYSCALL so it is validated even when the tracepoint is disabled. --- include/linux/tracepoint.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 906f3091d23d..425123e921ac 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -301,6 +301,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(t= racepoint_ptr_t *p) __DECLARE_TRACE_COMMON(name, PARAMS(proto), PARAMS(args), cond, PARAMS(da= ta_proto)) \ static inline void trace_##name(proto) \ { \ + might_fault(); \ if (static_branch_unlikely(&__tracepoint_##name.key)) \ __DO_TRACE(name, \ TP_ARGS(args), \ --=20 2.39.5