Revision a930d8790552658140d7d0d2e316af4f0d76a512 authored by Al Viro on 12 March 2013, 02:59:49 UTC, committed by Linus Torvalds on 12 March 2013, 15:29:17 UTC
If you open a pipe for neither read nor write, the pipe code will not
add any usage counters to the pipe, causing the 'struct pipe_inode_info"
to be potentially released early.

That doesn't normally matter, since you cannot actually use the pipe,
but the pipe release code - particularly fasync handling - still expects
the actual pipe infrastructure to all be there.  And rather than adding
NULL pointer checks, let's just disallow this case, the same way we
already do for the named pipe ("fifo") case.

This is ancient going back to pre-2.4 days, and until trinity, nobody
naver noticed.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 7c6baa3
Raw File
sound_firmware.c
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <asm/uaccess.h>
#include "oss/sound_firmware.h"

static int do_mod_firmware_load(const char *fn, char **fp)
{
	struct file* filp;
	long l;
	char *dp;
	loff_t pos;

	filp = filp_open(fn, 0, 0);
	if (IS_ERR(filp))
	{
		printk(KERN_INFO "Unable to load '%s'.\n", fn);
		return 0;
	}
	l = i_size_read(file_inode(filp));
	if (l <= 0 || l > 131072)
	{
		printk(KERN_INFO "Invalid firmware '%s'\n", fn);
		filp_close(filp, NULL);
		return 0;
	}
	dp = vmalloc(l);
	if (dp == NULL)
	{
		printk(KERN_INFO "Out of memory loading '%s'.\n", fn);
		filp_close(filp, NULL);
		return 0;
	}
	pos = 0;
	if (vfs_read(filp, dp, l, &pos) != l)
	{
		printk(KERN_INFO "Failed to read '%s'.\n", fn);
		vfree(dp);
		filp_close(filp, NULL);
		return 0;
	}
	filp_close(filp, NULL);
	*fp = dp;
	return (int) l;
}

/**
 *	mod_firmware_load - load sound driver firmware
 *	@fn: filename
 *	@fp: return for the buffer.
 *
 *	Load the firmware for a sound module (up to 128K) into a buffer.
 *	The buffer is returned in *fp. It is allocated with vmalloc so is
 *	virtually linear and not DMAable. The caller should free it with
 *	vfree when finished.
 *
 *	The length of the buffer is returned on a successful load, the
 *	value zero on a failure.
 *
 *	Caution: This API is not recommended. Firmware should be loaded via
 *	request_firmware.
 */
 
int mod_firmware_load(const char *fn, char **fp)
{
	int r;
	mm_segment_t fs = get_fs();

	set_fs(get_ds());
	r = do_mod_firmware_load(fn, fp);
	set_fs(fs);
	return r;
}
EXPORT_SYMBOL(mod_firmware_load);

MODULE_LICENSE("GPL");
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