From 41bc46c12a8053a1b3279a379bd6b5e87b045b85 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Thu, 7 Sep 2023 22:06:51 +0200 Subject: bpf: Add override check to kprobe multi link attach Currently the multi_kprobe link attach does not check error injection list for programs with bpf_override_return helper and allows them to attach anywhere. Adding the missing check. Fixes: 0dcac2725406 ("bpf: Add multi kprobe link") Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Reviewed-by: Alan Maguire Cc: stable@vger.kernel.org Link: https://lore.kernel.org/bpf/20230907200652.926951-1-jolsa@kernel.org --- kernel/trace/bpf_trace.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a7264b2c17ad..c1c1af63ced2 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2853,6 +2853,17 @@ static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u3 return arr.mods_cnt; } +static int addrs_check_error_injection_list(unsigned long *addrs, u32 cnt) +{ + u32 i; + + for (i = 0; i < cnt; i++) { + if (!within_error_injection_list(addrs[i])) + return -EINVAL; + } + return 0; +} + int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { struct bpf_kprobe_multi_link *link = NULL; @@ -2930,6 +2941,11 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr goto error; } + if (prog->kprobe_override && addrs_check_error_injection_list(addrs, cnt)) { + err = -EINVAL; + goto error; + } + link = kzalloc(sizeof(*link), GFP_KERNEL); if (!link) { err = -ENOMEM; -- cgit v1.2.3 From 57eb5e1c5c57972c95e8efab6bc81b87161b0b07 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Fri, 15 Sep 2023 12:14:20 +0200 Subject: bpf: Fix uprobe_multi get_pid_task error path Dan reported Smatch static checker warning due to missing error value set in uprobe multi link's get_pid_task error path. Reported-by: Dan Carpenter Closes: https://lore.kernel.org/bpf/c5ffa7c0-6b06-40d5-aca2-63833b5cd9af@moroto.mountain/ Signed-off-by: Jiri Olsa Reviewed-by: Song Liu Link: https://lore.kernel.org/r/20230915101420.1193800-1-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- kernel/trace/bpf_trace.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'kernel/trace') diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index c1c1af63ced2..868008f56fec 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3223,8 +3223,10 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr rcu_read_lock(); task = get_pid_task(find_vpid(pid), PIDTYPE_PID); rcu_read_unlock(); - if (!task) + if (!task) { + err = -ESRCH; goto error_path_put; + } } err = -ENOMEM; -- cgit v1.2.3