From: NeilBrown Date: Thu, 30 Jul 2015 03:00:56 +0000 (+1000) Subject: NFSv4: don't set SETATTR for O_RDONLY|O_EXCL X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=efcbc04e16dfa95fef76309f89710dd1d99a5453;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git NFSv4: don't set SETATTR for O_RDONLY|O_EXCL It is unusual to combine the open flags O_RDONLY and O_EXCL, but it appears that libre-office does just that. [pid 3250] stat("/home/USER/.config", {st_mode=S_IFDIR|0700, st_size=8192, ...}) = 0 [pid 3250] open("/home/USER/.config/libreoffice/4-suse/user/extensions/buildid", O_RDONLY|O_EXCL NFSv4 takes O_EXCL as a sign that a setattr command should be sent, probably to reset the timestamps. When it was an O_RDONLY open, the SETATTR command does not identify any actual attributes to change. If no delegation was provided to the open, the SETATTR uses the all-zeros stateid and the request is accepted (at least by the Linux NFS server - no harm, no foul). If a read-delegation was provided, this is used in the SETATTR request, and a Netapp filer will justifiably claim NFS4ERR_BAD_STATEID, which the Linux client takes as a sign to retry - indefinitely. So only treat O_EXCL specially if O_CREAT was also given. Signed-off-by: NeilBrown Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 3acb1eb72930..15ee8bd99b61 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2425,7 +2425,7 @@ static int _nfs4_do_open(struct inode *dir, goto err_free_label; state = ctx->state; - if ((opendata->o_arg.open_flags & O_EXCL) && + if ((opendata->o_arg.open_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL) && (opendata->o_arg.createmode != NFS4_CREATE_GUARDED)) { nfs4_exclusive_attrset(opendata, sattr);