lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 27 Jun 2019 16:53:54 +0530 From: "Naveen N. Rao" <naveen.n.rao@...ux.vnet.ibm.com> To: Michael Ellerman <mpe@...erman.id.au>, Steven Rostedt <rostedt@...dmis.org>, Masami Hiramatsu <mhiramat@...nel.org>, Ingo Molnar <mingo@...nel.org>, Nicholas Piggin <npiggin@...il.com> Cc: <linuxppc-dev@...ts.ozlabs.org>, <linux-kernel@...r.kernel.org> Subject: [PATCH v2 6/7] kprobes/ftrace: Use ftrace_location() when [dis]arming probes Ftrace location could include more than a single instruction in case of some architectures (powerpc64, for now). In this case, kprobe is permitted on any of those instructions, and uses ftrace infrastructure for functioning. However, [dis]arm_kprobe_ftrace() uses the kprobe address when setting up ftrace filter IP. This won't work if the address points to any instruction apart from the one that has a branch to _mcount(). To resolve this, have [dis]arm_kprobe_ftrace() use ftrace_function() to identify the filter IP. Acked-by: Masami Hiramatsu <mhiramat@...nel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@...ux.vnet.ibm.com> --- kernel/kprobes.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 445337c107e0..282ee704e2d8 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -978,10 +978,10 @@ static int prepare_kprobe(struct kprobe *p) /* Caller must lock kprobe_mutex */ static int arm_kprobe_ftrace(struct kprobe *p) { + unsigned long ftrace_ip = ftrace_location((unsigned long)p->addr); int ret = 0; - ret = ftrace_set_filter_ip(&kprobe_ftrace_ops, - (unsigned long)p->addr, 0, 0); + ret = ftrace_set_filter_ip(&kprobe_ftrace_ops, ftrace_ip, 0, 0); if (ret) { pr_debug("Failed to arm kprobe-ftrace at %pS (%d)\n", p->addr, ret); @@ -1005,13 +1005,14 @@ static int arm_kprobe_ftrace(struct kprobe *p) * non-empty filter_hash for IPMODIFY ops, we're safe from an accidental * empty filter_hash which would undesirably trace all functions. */ - ftrace_set_filter_ip(&kprobe_ftrace_ops, (unsigned long)p->addr, 1, 0); + ftrace_set_filter_ip(&kprobe_ftrace_ops, ftrace_ip, 1, 0); return ret; } /* Caller must lock kprobe_mutex */ static int disarm_kprobe_ftrace(struct kprobe *p) { + unsigned long ftrace_ip = ftrace_location((unsigned long)p->addr); int ret = 0; if (kprobe_ftrace_enabled == 1) { @@ -1022,8 +1023,7 @@ static int disarm_kprobe_ftrace(struct kprobe *p) kprobe_ftrace_enabled--; - ret = ftrace_set_filter_ip(&kprobe_ftrace_ops, - (unsigned long)p->addr, 1, 0); + ret = ftrace_set_filter_ip(&kprobe_ftrace_ops, ftrace_ip, 1, 0); WARN_ONCE(ret < 0, "Failed to disarm kprobe-ftrace at %pS (%d)\n", p->addr, ret); return ret; -- 2.22.0
Powered by blists - more mailing lists