* [PATCH bpf-next 1/2] libbpf: fix memory leak in legacy kprobe attach logic
@ 2021-09-20 18:19 Andrii Nakryiko
2021-09-20 18:19 ` [PATCH bpf-next 2/2] libbpf: fix legacy kprobe event creation FD error handling Andrii Nakryiko
0 siblings, 1 reply; 3+ messages in thread
From: Andrii Nakryiko @ 2021-09-20 18:19 UTC (permalink / raw)
To: bpf, ast, daniel; +Cc: andrii, kernel-team
In some error scenarios legacy_probe string won't be free()'d. Fix this.
This was reported by Coverity static analysis.
Fixes: ca304b40c20d ("libbpf: Introduce legacy kprobe events support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
tools/lib/bpf/libbpf.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index da65a1666a5e..6d2f12db6034 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9365,10 +9365,11 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
offset, -1 /* pid */);
}
if (pfd < 0) {
+ err = pfd;
pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n",
prog->name, retprobe ? "kretprobe" : "kprobe", func_name,
- libbpf_strerror_r(pfd, errmsg, sizeof(errmsg)));
- return libbpf_err_ptr(pfd);
+ libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+ goto err_out;
}
link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts);
err = libbpf_get_error(link);
@@ -9377,7 +9378,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
pr_warn("prog '%s': failed to attach to %s '%s': %s\n",
prog->name, retprobe ? "kretprobe" : "kprobe", func_name,
libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
- return libbpf_err_ptr(err);
+ goto err_out;
}
if (legacy) {
struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link);
@@ -9387,6 +9388,9 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
}
return link;
+err_out:
+ free(legacy_probe);
+ return libbpf_err_ptr(err);
}
struct bpf_link *bpf_program__attach_kprobe(const struct bpf_program *prog,
--
2.30.2
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH bpf-next 2/2] libbpf: fix legacy kprobe event creation FD error handling
2021-09-20 18:19 [PATCH bpf-next 1/2] libbpf: fix memory leak in legacy kprobe attach logic Andrii Nakryiko
@ 2021-09-20 18:19 ` Andrii Nakryiko
2021-09-20 23:23 ` Andrii Nakryiko
0 siblings, 1 reply; 3+ messages in thread
From: Andrii Nakryiko @ 2021-09-20 18:19 UTC (permalink / raw)
To: bpf, ast, daniel; +Cc: andrii, kernel-team
open() returns -1 on error, not zero FD. Fix the error handling logic.
Reported by Coverity statis analysis.
Fixes: ca304b40c20d ("libbpf: Introduce legacy kprobe events support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
tools/lib/bpf/libbpf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 6d2f12db6034..761497be6ffc 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9036,7 +9036,7 @@ static int poke_kprobe_events(bool add, const char *name, bool retprobe, uint64_
}
fd = open(file, O_WRONLY | O_APPEND, 0);
- if (!fd)
+ if (fd < 0)
return -errno;
ret = write(fd, cmd, strlen(cmd));
if (ret < 0)
--
2.30.2
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH bpf-next 2/2] libbpf: fix legacy kprobe event creation FD error handling
2021-09-20 18:19 ` [PATCH bpf-next 2/2] libbpf: fix legacy kprobe event creation FD error handling Andrii Nakryiko
@ 2021-09-20 23:23 ` Andrii Nakryiko
0 siblings, 0 replies; 3+ messages in thread
From: Andrii Nakryiko @ 2021-09-20 23:23 UTC (permalink / raw)
To: Andrii Nakryiko; +Cc: bpf, Alexei Starovoitov, Daniel Borkmann, Kernel Team
On Mon, Sep 20, 2021 at 11:20 AM Andrii Nakryiko <andrii@kernel.org> wrote:
>
> open() returns -1 on error, not zero FD. Fix the error handling logic.
> Reported by Coverity statis analysis.
>
> Fixes: ca304b40c20d ("libbpf: Introduce legacy kprobe events support")
> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> ---
This patch is superseded by a new patch series ([0]), please don't apply.
[0] https://patchwork.kernel.org/project/netdevbpf/list/?series=550083&state=*
> tools/lib/bpf/libbpf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 6d2f12db6034..761497be6ffc 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -9036,7 +9036,7 @@ static int poke_kprobe_events(bool add, const char *name, bool retprobe, uint64_
> }
>
> fd = open(file, O_WRONLY | O_APPEND, 0);
> - if (!fd)
> + if (fd < 0)
> return -errno;
> ret = write(fd, cmd, strlen(cmd));
> if (ret < 0)
> --
> 2.30.2
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-09-21 1:59 UTC | newest]
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