Hi, After upgrading my machine to Ubuntu 16.04, I noticed that 'git clone' started creating files with wrong mode (0700 instead of 0644 typically) on NFSv4 partitions mounted from our NetApp servers. I've first tracked this down to the fact that git uses open(name, O_RDWR|O_CREAT|O_EXCL, 0666); to create files. If O_EXCL is not present, the files are created normally. I've tried various kernels from Ubuntu and the problems appeared between their 4.2.0-42-generic kernel-image (as found on willy) and the 4.4.0 kernels found on xenial. I tried building 4.9 from kernel.org and the problem is also there. I've then bisected the kernel to figure out that this is caused by the following commit: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5334c5bdac926c5f8d89729beccb46fe88eda9e7 ie NFS: Send attributes in OPEN request for NFS4_CREATE_EXCLUSIVE4_1 Our NetApp filers are running: NetApp Release 8.2.3P3 7-Mode: Tue Apr 28 14:48:22 PDT 2015 Any idea on how to fix the problem (either on the NetApp side, or on Linux kernel side)? Appended is a small program to reproduce the issue: Thanks in advance, #include <sys/types.h> #include <sys/stat.h> #include <err.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> /* * Demonstrate file creation bug on NFS v4 and linux kernel 4.4+ * * mktemp() is used on purpose. */ int main(int argc, char *argv[]) { const char *name = argv[1]; char tmp[] = "./tmpXXXXXXXXXX"; struct stat buf; mode_t expected; int fd, i, n = 40; umask(S_IWGRP | S_IWOTH); expected = 0666 & ~(S_IWGRP | S_IWOTH); if (argv[1] == NULL) name = mktemp(tmp); for (i = 0; i < n; i++) { fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0666); if (fd < 0) err(1, "open %s", name); memset(&buf, 0, sizeof(buf)); if (stat(name, &buf) < 0) err(1, "stat %s", name); if ((buf.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)) != expected) printf("%s: %o\n", name, (int)buf.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)); else printf("%s: ok\n", name); unlink(name); } exit(0); } -- Matthieu Herrb
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