lkml.org 
[lkml]   [2003]   [Mar]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH] readlink in /proc w/ overlong path
> Trying to read the overlong target of a /proc/*/fd/N file descriptor
> leads with the current BK kernel to a segfault in the kernel.

Yes. Below a patch.

Andries

diff -u --recursive --new-file -X /linux/dontdiff a/fs/proc/base.c b/fs/proc/base.c
--- a/fs/proc/base.c Sun Feb 23 22:47:55 2003
+++ b/fs/proc/base.c Sun Mar 30 14:32:35 2003
@@ -565,10 +565,10 @@
}

static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
- char * buffer, int buflen)
+ char *buffer, int buflen)
{
struct inode * inode;
- char * tmp = (char*)__get_free_page(GFP_KERNEL), *path;
+ char *tmp = (char*)__get_free_page(GFP_KERNEL), *path;
int len;

if (!tmp)
@@ -576,13 +576,17 @@

inode = dentry->d_inode;
path = d_path(dentry, mnt, tmp, PAGE_SIZE);
+ len = PTR_ERR(path);
+ if (IS_ERR(path))
+ goto out;
len = tmp + PAGE_SIZE - 1 - path;

- if (len < buflen)
- buflen = len;
- copy_to_user(buffer, path, buflen);
+ if (len > buflen)
+ len = buflen;
+ copy_to_user(buffer, path, len);
+ out:
free_page((unsigned long)tmp);
- return buflen;
+ return len;
}

static int proc_pid_readlink(struct dentry * dentry, char * buffer, int buflen)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2005-03-22 13:34    [W:0.026 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site