Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755971AbbGPBmp (ORCPT ); Wed, 15 Jul 2015 21:42:45 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:55894 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754327AbbGPBLI (ORCPT ); Wed, 15 Jul 2015 21:11:08 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Eric Sandeen , Dave Chinner , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 147/251] xfs: fix remote symlinks on V5/CRC filesystems Date: Wed, 15 Jul 2015 18:07:48 -0700 Message-Id: <1437008972-9140-148-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1437008972-9140-1-git-send-email-kamal@canonical.com> References: <1437008972-9140-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1832 Lines: 57 3.19.8-ckt4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Sandeen commit 2ac56d3d4bd625450a54d4c3f9292d58f6b88232 upstream. If we create a CRC filesystem, mount it, and create a symlink with a path long enough that it can't live in the inode, we get a very strange result upon remount: # ls -l mnt total 4 lrwxrwxrwx. 1 root root 929 Jun 15 16:58 link -> XSLM XSLM is the V5 symlink block header magic (which happens to be followed by a NUL, so the string looks terminated). xfs_readlink_bmap() advanced cur_chunk by the size of the header for CRC filesystems, but never actually used that pointer; it kept reading from bp->b_addr, which is the start of the block, rather than the start of the symlink data after the header. Looks like this problem goes back to v3.10. Fixing this gets us reading the proper link target, again. Signed-off-by: Eric Sandeen Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner Signed-off-by: Kamal Mostafa --- fs/xfs/xfs_symlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c index 25791df..e0b50ed 100644 --- a/fs/xfs/xfs_symlink.c +++ b/fs/xfs/xfs_symlink.c @@ -104,7 +104,7 @@ xfs_readlink_bmap( cur_chunk += sizeof(struct xfs_dsymlink_hdr); } - memcpy(link + offset, bp->b_addr, byte_cnt); + memcpy(link + offset, cur_chunk, byte_cnt); pathlen -= byte_cnt; offset += byte_cnt; -- 1.9.1 -- 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/