Commit e3912ac3 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Linus Torvalds
Browse files

proc: use %u for pid printing and slightly less stack 

PROC_NUMBUF is 13 which is enough for "negative int + \n + \0".

However PIDs and TGIDs are never negative and newline is not a concern,
so use just 10 per integer.

Link: http://lkml.kernel.org/r/20171120203005.GA27743@avx2


Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Cc: Alexander Viro <viro@ftp.linux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 48c23239

fs/proc/base.c

+8 −8
Original line number Diff line number Diff line
@@ -3018,11 +3018,11 @@ static const struct inode_operations proc_tgid_base_inode_operations = { 
static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)

{

	struct dentry *dentry, *leader, *dir;

	char buf[PROC_NUMBUF];

	char buf[10 + 1];

	struct qstr name;



	name.name = buf;

	name.len = snprintf(buf, sizeof(buf), "%d", pid);

	name.len = snprintf(buf, sizeof(buf), "%u", pid);

	/* no ->d_hash() rejects on procfs */

	dentry = d_hash_and_lookup(mnt->mnt_root, &name);

	if (dentry) {
@@ -3034,7 +3034,7 @@ static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 
		return;



	name.name = buf;

	name.len = snprintf(buf, sizeof(buf), "%d", tgid);

	name.len = snprintf(buf, sizeof(buf), "%u", tgid);

	leader = d_hash_and_lookup(mnt->mnt_root, &name);

	if (!leader)

		goto out;
@@ -3046,7 +3046,7 @@ static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 
		goto out_put_leader;



	name.name = buf;

	name.len = snprintf(buf, sizeof(buf), "%d", pid);

	name.len = snprintf(buf, sizeof(buf), "%u", pid);

	dentry = d_hash_and_lookup(dir, &name);

	if (dentry) {

		d_invalidate(dentry);
@@ -3225,14 +3225,14 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx) 
	for (iter = next_tgid(ns, iter);

	     iter.task;

	     iter.tgid += 1, iter = next_tgid(ns, iter)) {

		char name[PROC_NUMBUF];

		char name[10 + 1];

		int len;



		cond_resched();

		if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE))

			continue;



		len = snprintf(name, sizeof(name), "%d", iter.tgid);

		len = snprintf(name, sizeof(name), "%u", iter.tgid);

		ctx->pos = iter.tgid + TGID_OFFSET;

		if (!proc_fill_cache(file, ctx, name, len,

				     proc_pid_instantiate, iter.task, NULL)) {
@@ -3560,10 +3560,10 @@ static int proc_task_readdir(struct file *file, struct dir_context *ctx) 
	for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);

	     task;

	     task = next_tid(task), ctx->pos++) {

		char name[PROC_NUMBUF];

		char name[10 + 1];

		int len;

		tid = task_pid_nr_ns(task, ns);

		len = snprintf(name, sizeof(name), "%d", tid);

		len = snprintf(name, sizeof(name), "%u", tid);

		if (!proc_fill_cache(file, ctx, name, len,

				proc_task_instantiate, task, NULL)) {

			/* returning this tgid failed, save it as the first

fs/proc/fd.c

+1 −1
Original line number Diff line number Diff line
@@ -236,7 +236,7 @@ static int proc_readfd_common(struct file *file, struct dir_context *ctx, 
	for (fd = ctx->pos - 2;

	     fd < files_fdtable(files)->max_fds;

	     fd++, ctx->pos++) {

		char name[PROC_NUMBUF];

		char name[10 + 1];

		int len;



		if (!fcheck_files(files, fd))

fs/proc/self.c

+3 −3
Original line number Diff line number Diff line
@@ -17,11 +17,11 @@ static const char *proc_self_get_link(struct dentry *dentry, 


	if (!tgid)

		return ERR_PTR(-ENOENT);

	/* 11 for max length of signed int in decimal + NULL term */

	name = kmalloc(12, dentry ? GFP_KERNEL : GFP_ATOMIC);

	/* max length of unsigned int in decimal + NULL term */

	name = kmalloc(10 + 1, dentry ? GFP_KERNEL : GFP_ATOMIC);

	if (unlikely(!name))

		return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD);

	sprintf(name, "%d", tgid);

	sprintf(name, "%u", tgid);

	set_delayed_call(done, kfree_link, name);

	return name;

}

fs/proc/thread_self.c

+2 −3
Original line number Diff line number Diff line
@@ -18,11 +18,10 @@ static const char *proc_thread_self_get_link(struct dentry *dentry, 


	if (!pid)

		return ERR_PTR(-ENOENT);

	name = kmalloc(PROC_NUMBUF + 6 + PROC_NUMBUF,

				dentry ? GFP_KERNEL : GFP_ATOMIC);

	name = kmalloc(10 + 6 + 10 + 1, dentry ? GFP_KERNEL : GFP_ATOMIC);

	if (unlikely(!name))

		return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD);

	sprintf(name, "%d/task/%d", tgid, pid);

	sprintf(name, "%u/task/%u", tgid, pid);

	set_delayed_call(done, kfree_link, name);

	return name;

}

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