From 20d1999d42392063fd530d1f6c00b93c25d178d6 Mon Sep 17 00:00:00 2001 From: Francis Deslauriers Date: Thu, 12 Dec 2019 09:32:00 -0500 Subject: [PATCH] liblttng-ust-comm: move `_unlock_fd_tracker()` after `close()` on error paths Right now, receiving an error from `lttng_ust_add_fd_to_tracker()` means that the fd was _not_ added to the fd set. So the `lttng_ust_safe_close_fd()` (overriding `close()`) call will indeed close the fd as expected. So, it doesn't matter if the `close()` is before or after the `_unlock_`. Even considering that, I believe that it's clearer and more common to have all related operations within the `_lock_` and `_unlock_` functions. Also, `lttng_ust_add_fd_to_tracker()` might be modified in the future and fail for some other reason. Signed-off-by: Francis Deslauriers Signed-off-by: Mathieu Desnoyers Change-Id: Id29a6ab004cfd5ca601615e1a70c74cf754b12e2 --- liblttng-ust-comm/lttng-ust-comm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/liblttng-ust-comm/lttng-ust-comm.c b/liblttng-ust-comm/lttng-ust-comm.c index 543465ed..9f2bdd5b 100644 --- a/liblttng-ust-comm/lttng-ust-comm.c +++ b/liblttng-ust-comm/lttng-ust-comm.c @@ -631,12 +631,12 @@ ssize_t ustcomm_recv_channel_from_sessiond(int sock, ret = lttng_ust_add_fd_to_tracker(wakeup_fd); if (ret < 0) { - lttng_ust_unlock_fd_tracker(); ret = close(wakeup_fd); if (ret) { PERROR("close on wakeup_fd"); } len = -EIO; + lttng_ust_unlock_fd_tracker(); goto error_recv; } @@ -677,19 +677,18 @@ int ustcomm_recv_stream_from_sessiond(int sock, ret = lttng_ust_add_fd_to_tracker(fds[0]); if (ret < 0) { - lttng_ust_unlock_fd_tracker(); ret = close(fds[0]); if (ret) { PERROR("close on received shm_fd"); } ret = -EIO; + lttng_ust_unlock_fd_tracker(); goto error; } *shm_fd = ret; ret = lttng_ust_add_fd_to_tracker(fds[1]); if (ret < 0) { - lttng_ust_unlock_fd_tracker(); ret = close(*shm_fd); if (ret) { PERROR("close on shm_fd"); @@ -700,6 +699,7 @@ int ustcomm_recv_stream_from_sessiond(int sock, PERROR("close on received wakeup_fd"); } ret = -EIO; + lttng_ust_unlock_fd_tracker(); goto error; } *wakeup_fd = ret; -- 2.34.1