From 40fe89c6e83791f1f9cd079d7d6b51598c4a5925 Mon Sep 17 00:00:00 2001 From: Lukasz Majewski Date: Sun, 27 Aug 2017 13:46:22 +0200 Subject: [PATCH] fix: fw_env: Prevent writing error message on special files, which don't support fsync According to fsync specification [1] some special files (e.g., a pipe, FIFO, or socket) don't support synchronization and return either EROFS or EINVAL. On the linux side the sys_fsync -> do_fsync() checks if the requested file has f_op->fsync defined. If not it returns EINVAL [2]. This commit prevents writing error messages for files (devices), which do not support fsync(). [1] - http://man7.org/linux/man-pages/man2/fsync.2.html [2] - http://elixir.free-electrons.com/linux/v4.13-rc6/source/fs/sync.c#L183 Signed-off-by: Lukasz Majewski Acked-by: Michael Heimpold --- tools/env/fw_env.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c index e50c075559..965e1662d7 100644 --- a/tools/env/fw_env.c +++ b/tools/env/fw_env.c @@ -1088,14 +1088,16 @@ static int flash_io (int mode) rc = flash_write (fd_current, fd_target, dev_target); - if (fsync (fd_current)) { + if (fsync(fd_current) && + !(errno == EINVAL || errno == EROFS)) { fprintf (stderr, "fsync failed on %s: %s\n", DEVNAME (dev_current), strerror (errno)); } if (HaveRedundEnv) { - if (fsync (fd_target)) { + if (fsync(fd_target) && + !(errno == EINVAL || errno == EROFS)) { fprintf (stderr, "fsync failed on %s: %s\n", DEVNAME (dev_current), strerror (errno)); -- 2.39.5