Bug#283241: kernel-image-2.6.8-1-k7: 2.6.8 and 2.6.9: utime(2) hangs on smbfs

[Christoph Hellwig <hch@lst.de>]

On Sat, Jan 08, 2005 at 06:36:27PM +0100, S?ren Hansen wrote:
> This bug does not exist in the vanilla version of 2.6.8. A patch added
> somewhere in the Debian kernel-source-2.6.8 packages breaks it. I,
> however, cannot seem to find any patches that should touch smbfs, so I
> can't point it out. I just just rebuilt that particular module with the
> sources from kernel.org and everything works just as well as before.
> 
> I believe this bug is severe enough to force a fix in Sarge! It renders
> smbfs TOTALLY useless.
> 
> -- 
> S??ren Hansen <sh@warma.dk>

When merging to 2.6.10 I noticed we have a bunch of smbfs changes that
were labelled security fixes.  Can you try to rebuild the kernel (or
just smbfs.ko) with the patch below reversed?

#! /bin/sh -e
## <PATCHNAME>.dpatch by <PATCH_AUTHOR@EMAI>
##
## All lines beginning with `## DP:' are a description of the patch.
## DP: Description: SMBfs overflow fixes
## DP: Patch author: unknown, stolen from -ac tree (probably Stefan Esser,  Juan Quintela, and Urban Widmark)
## DP: Upstream status: unknown

. $(dirname $0)/DPATCH

@DPATCH@
diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.9/fs/smbfs/proc.c linux-2.6.9/fs/smbfs/proc.c
--- linux.vanilla-2.6.9/fs/smbfs/proc.c	2004-10-20 23:17:20.000000000 +0100
+++ linux-2.6.9/fs/smbfs/proc.c	2004-11-17 19:41:41.000000000 +0000
@@ -1427,9 +1427,9 @@
 	 * So we must first calculate the amount of padding used by the server.
 	 */
 	data_off -= hdrlen;
-	if (data_off > SMB_READX_MAX_PAD) {
-		PARANOIA("offset is larger than max pad!\n");
-		PARANOIA("%d > %d\n", data_off, SMB_READX_MAX_PAD);
+	if (data_off > SMB_READX_MAX_PAD || data_off < 0) {
+		PARANOIA("offset is larger than SMB_READX_MAX_PAD or negative!\n");
+		PARANOIA("%d > %d || %d < 0\n", data_off, SMB_READX_MAX_PAD, data_off);
 		req->rq_rlen = req->rq_bufsize + 1;
 		return;
 	}
diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.9/fs/smbfs/request.c linux-2.6.9/fs/smbfs/request.c
--- linux.vanilla-2.6.9/fs/smbfs/request.c	2004-10-20 22:33:50.000000000 +0100
+++ linux-2.6.9/fs/smbfs/request.c	2004-11-17 19:41:41.000000000 +0000
@@ -588,6 +588,10 @@
 	data_count  = WVAL(inbuf, smb_drcnt);
 
 	/* Modify offset for the split header/buffer we use */
+	if (data_offset < hdrlen)
+		goto out_bad_data;
+	if (parm_offset < hdrlen)
+		goto out_bad_parm;
 	data_offset -= hdrlen;
 	parm_offset -= hdrlen;
 
@@ -607,6 +611,10 @@
 		req->rq_lparm = parm_count;
 		req->rq_data = req->rq_buffer + data_offset;
 		req->rq_parm = req->rq_buffer + parm_offset;
+		if (parm_offset + parm_count > req->rq_rlen)
+			goto out_bad_parm;
+		if (data_offset + data_count > req->rq_rlen)
+			goto out_bad_data;
 		return 0;
 	}
 
@@ -643,8 +652,12 @@
 
 	if (parm_disp + parm_count > req->rq_total_parm)
 		goto out_bad_parm;
+	if (parm_offset + parm_count > req->rq_rlen)
+		goto out_bad_parm;
 	if (data_disp + data_count > req->rq_total_data)
 		goto out_bad_data;
+	if (data_offset + data_count > req->rq_rlen)
+		goto out_bad_data;
 
 	inbuf = req->rq_buffer;
 	memcpy(req->rq_parm + parm_disp, inbuf + parm_offset, parm_count);
@@ -676,13 +692,13 @@
 	req->rq_errno = -EIO;
 	goto out;
 out_bad_parm:
-	printk(KERN_ERR "smb_trans2: invalid parms, disp=%d, cnt=%d, tot=%d\n",
-	       parm_disp, parm_count, parm_tot);
+	printk(KERN_ERR "smb_trans2: invalid parms, disp=%d, cnt=%d, tot=%d, ofs=%d\n",
+	       parm_disp, parm_count, parm_tot, parm_offset);
 	req->rq_errno = -EIO;
 	goto out;
 out_bad_data:
-	printk(KERN_ERR "smb_trans2: invalid data, disp=%d, cnt=%d, tot=%d\n",
-	       data_disp, data_count, data_tot);
+	printk(KERN_ERR "smb_trans2: invalid data, disp=%d, cnt=%d, tot=%d, ofs=%d\n",
+	       data_disp, data_count, data_tot, data_offset);
 	req->rq_errno = -EIO;
 out:
 	return req->rq_errno;