diff options
| author |   Xin Liu <liuxin350@huawei.com> | 2022-12-23 21:36:18 +0800 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2022-12-28 14:03:51 -0800 |
| commit | 07453245620c075779abefa2a9f469fa336e7510 (patch) | |
| tree | 27d0c2b236c8e450653d4ed66dc48dac97a85f5f /tools/lib/bpf/libbpf_internal.h | |
| parent | bpf: fix regs_exact() logic in regsafe() to remap IDs correctly (diff) | |
| download | wireguard-linux-07453245620c075779abefa2a9f469fa336e7510.tar.xz wireguard-linux-07453245620c075779abefa2a9f469fa336e7510.zip | |
libbpf: fix errno is overwritten after being closed.
In the ensure_good_fd function, if the fcntl function succeeds but
the close function fails, ensure_good_fd returns a normal fd and
sets errno, which may cause users to misunderstand. The close
failure is not a serious problem, and the correct FD has been
handed over to the upper-layer application. Let's restore errno here.
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Link: https://lore.kernel.org/r/20221223133618.10323-1-liuxin350@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/lib/bpf/libbpf_internal.h')
| -rw-r--r-- | tools/lib/bpf/libbpf_internal.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 377642ff51fc..98333a6c38e9 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -543,10 +543,9 @@ static inline int ensure_good_fd(int fd) fd = fcntl(fd, F_DUPFD_CLOEXEC, 3); saved_errno = errno; close(old_fd); - if (fd < 0) { + errno = saved_errno; + if (fd < 0) pr_warn("failed to dup FD %d to FD > 2: %d\n", old_fd, -saved_errno); - errno = saved_errno; - } } return fd; } |