From 1117f72ea0217ba0cc19f05adbbd8b9a397f5ab7 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 6 Aug 2011 11:51:33 -0700 Subject: [PATCH] vfs: show O_CLOEXE bit properly in /proc//fdinfo/ files The CLOEXE bit is magical, and for performance (and semantic) reasons we don't actually maintain it in the file descriptor itself, but in a separate bit array. Which means that when we show f_flags, the CLOEXE status is shown incorrectly: we show the status not as it is now, but as it was when the file was opened. Fix that by looking up the bit properly in the 'fdt->close_on_exec' bit array. Uli needs this in order to re-implement the pfiles program: "For normal file descriptors (not sockets) this was the last piece of information which wasn't available. This is all part of my 'give Solaris users no reason to not switch' effort. I intend to offer the code to the util-linux-ng maintainers." Requested-by: Ulrich Drepper Signed-off-by: Linus Torvalds --- fs/proc/base.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 73a562bf7266..5eb02069e1b8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1919,6 +1919,14 @@ static int proc_fd_info(struct inode *inode, struct path *path, char *info) spin_lock(&files->file_lock); file = fcheck_files(files, fd); if (file) { + unsigned int f_flags; + struct fdtable *fdt; + + fdt = files_fdtable(files); + f_flags = file->f_flags & ~O_CLOEXEC; + if (FD_ISSET(fd, fdt->close_on_exec)) + f_flags |= O_CLOEXEC; + if (path) { *path = file->f_path; path_get(&file->f_path); @@ -1928,7 +1936,7 @@ static int proc_fd_info(struct inode *inode, struct path *path, char *info) "pos:\t%lli\n" "flags:\t0%o\n", (long long) file->f_pos, - file->f_flags); + f_flags); spin_unlock(&files->file_lock); put_files_struct(files); return 0; -- GitLab