This is a note to let you know that I've just added the patch titled staging/lustre/llite: move root_squash from sysfs to debugfs to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: staging-lustre-llite-move-root_squash-from-sysfs-to-debugfs.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 4c13990e35b9f053857d4ad83bf0f58e612ec414 Mon Sep 17 00:00:00 2001 From: Oleg Drokin <green@xxxxxxxxxxxxxx> Date: Wed, 7 Dec 2016 17:41:27 -0500 Subject: staging/lustre/llite: move root_squash from sysfs to debugfs From: Oleg Drokin <green@xxxxxxxxxxxxxx> commit 4c13990e35b9f053857d4ad83bf0f58e612ec414 upstream. root_squash control got accidentally moved to sysfs instead of debugfs, and the write side of it was also broken expecting a userspace buffer. It contains both uid and gid values in a single file, so debugfs is a clear place for it. Reported-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Fixes: c948390f10ccc "fix inconsistencies of root squash feature" Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx> Reviewed-by: James Simmons <jsimmons@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/lustre/lustre/llite/lproc_llite.c | 27 ++++++++++++---------- 1 file changed, 15 insertions(+), 12 deletions(-) --- a/drivers/staging/lustre/lustre/llite/lproc_llite.c +++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c @@ -924,27 +924,29 @@ static ssize_t ll_unstable_stats_seq_wri } LPROC_SEQ_FOPS(ll_unstable_stats); -static ssize_t root_squash_show(struct kobject *kobj, struct attribute *attr, - char *buf) +static int ll_root_squash_seq_show(struct seq_file *m, void *v) { - struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info, - ll_kobj); + struct super_block *sb = m->private; + struct ll_sb_info *sbi = ll_s2sbi(sb); struct root_squash_info *squash = &sbi->ll_squash; - return sprintf(buf, "%u:%u\n", squash->rsi_uid, squash->rsi_gid); + seq_printf(m, "%u:%u\n", squash->rsi_uid, squash->rsi_gid); + return 0; } -static ssize_t root_squash_store(struct kobject *kobj, struct attribute *attr, - const char *buffer, size_t count) +static ssize_t ll_root_squash_seq_write(struct file *file, + const char __user *buffer, + size_t count, loff_t *off) { - struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info, - ll_kobj); + struct seq_file *m = file->private_data; + struct super_block *sb = m->private; + struct ll_sb_info *sbi = ll_s2sbi(sb); struct root_squash_info *squash = &sbi->ll_squash; return lprocfs_wr_root_squash(buffer, count, squash, - ll_get_fsname(sbi->ll_sb, NULL, 0)); + ll_get_fsname(sb, NULL, 0)); } -LUSTRE_RW_ATTR(root_squash); +LPROC_SEQ_FOPS(ll_root_squash); static int ll_nosquash_nids_seq_show(struct seq_file *m, void *v) { @@ -997,6 +999,8 @@ static struct lprocfs_vars lprocfs_llite { "statahead_stats", &ll_statahead_stats_fops, NULL, 0 }, { "unstable_stats", &ll_unstable_stats_fops, NULL }, { "sbi_flags", &ll_sbi_flags_fops, NULL, 0 }, + { .name = "root_squash", + .fops = &ll_root_squash_fops }, { .name = "nosquash_nids", .fops = &ll_nosquash_nids_fops }, { NULL } @@ -1027,7 +1031,6 @@ static struct attribute *llite_attrs[] = &lustre_attr_max_easize.attr, &lustre_attr_default_easize.attr, &lustre_attr_xattr_cache.attr, - &lustre_attr_root_squash.attr, NULL, }; Patches currently in stable-queue which might be from green@xxxxxxxxxxxxxx are queue-4.9/staging-lustre-llite-move-root_squash-from-sysfs-to-debugfs.patch