From 99dc829256bb8cfcb1f58b7f118893fdbf608e60 Mon Sep 17 00:00:00 2001 From: Jerome Marchand Date: Tue, 26 Oct 2010 14:22:33 -0700 Subject: [PATCH] procfs: fix numbering in /proc/locks The lock number in /proc/locks (first field) is implemented by a counter (private field of struct seq_file) which is incremented at each call of locks_show() and reset to 1 in locks_start() whatever the offset is. It should be reset according to the actual position in the list. Because of this, the numbering erratically restarts at 1 several times when reading a long /proc/locks file. Moreover, locks_show() can be called twice to print a single line thus skipping a number. The counter should be incremented in locks_next(). And last, pos is a loff_t, which can be bigger than a pointer, so we don't use the pointer as an integer anymore, and allocate a loff_t instead. Signed-off-by: Jerome Marchand Cc: Pavel Emelyanov Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/locks.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index 8b2b6ad56a09..4de3a2666810 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2109,7 +2109,7 @@ EXPORT_SYMBOL_GPL(vfs_cancel_lock); #include static void lock_get_status(struct seq_file *f, struct file_lock *fl, - int id, char *pfx) + loff_t id, char *pfx) { struct inode *inode = NULL; unsigned int fl_pid; @@ -2122,7 +2122,7 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, if (fl->fl_file != NULL) inode = fl->fl_file->f_path.dentry->d_inode; - seq_printf(f, "%d:%s ", id, pfx); + seq_printf(f, "%lld:%s ", id, pfx); if (IS_POSIX(fl)) { seq_printf(f, "%6s %s ", (fl->fl_flags & FL_ACCESS) ? "ACCESS" : "POSIX ", @@ -2185,24 +2185,27 @@ static int locks_show(struct seq_file *f, void *v) fl = list_entry(v, struct file_lock, fl_link); - lock_get_status(f, fl, (long)f->private, ""); + lock_get_status(f, fl, *((loff_t *)f->private), ""); list_for_each_entry(bfl, &fl->fl_block, fl_block) - lock_get_status(f, bfl, (long)f->private, " ->"); + lock_get_status(f, bfl, *((loff_t *)f->private), " ->"); - f->private++; return 0; } static void *locks_start(struct seq_file *f, loff_t *pos) { + loff_t *p = f->private; + lock_flocks(); - f->private = (void *)1; + *p = (*pos + 1); return seq_list_start(&file_lock_list, *pos); } static void *locks_next(struct seq_file *f, void *v, loff_t *pos) { + loff_t *p = f->private; + ++*p; return seq_list_next(v, &file_lock_list, pos); } @@ -2220,14 +2223,14 @@ static const struct seq_operations locks_seq_operations = { static int locks_open(struct inode *inode, struct file *filp) { - return seq_open(filp, &locks_seq_operations); + return seq_open_private(filp, &locks_seq_operations, sizeof(loff_t)); } static const struct file_operations proc_locks_operations = { .open = locks_open, .read = seq_read, .llseek = seq_lseek, - .release = seq_release, + .release = seq_release_private, }; static int __init proc_locks_init(void) -- GitLab