lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 17 Sep 2012 01:36:54 +0100 From: Ben Hutchings <ben@...adent.org.uk> To: linux-kernel@...r.kernel.org, stable@...r.kernel.org Cc: torvalds@...ux-foundation.org, akpm@...ux-foundation.org, alan@...rguk.ukuu.org.uk, Jan Kara <jack@...e.cz>, Kristian Nielsen <knielsen@...elsen-hq.org> Subject: [ 029/135] ext3: Fix fdatasync() for files with only i_size changes 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara <jack@...e.cz> commit 156bddd8e505b295540f3ca0e27dda68cb0d49aa upstream. Code tracking when transaction needs to be committed on fdatasync(2) forgets to handle a situation when only inode's i_size is changed. Thus in such situations fdatasync(2) doesn't force transaction with new i_size to disk and that can result in wrong i_size after a crash. Fix the issue by updating inode's i_datasync_tid whenever its size is updated. Reported-by: Kristian Nielsen <knielsen@...elsen-hq.org> Signed-off-by: Jan Kara <jack@...e.cz> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@...adent.org.uk> --- fs/ext3/inode.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) --- a/fs/ext3/inode.c +++ b/fs/ext3/inode.c @@ -3072,6 +3072,8 @@ static int ext3_do_update_inode(handle_t struct ext3_inode_info *ei = EXT3_I(inode); struct buffer_head *bh = iloc->bh; int err = 0, rc, block; + int need_datasync = 0; + __le32 disksize; again: /* we can't allow multiple procs in here at once, its a bit racey */ @@ -3109,7 +3111,11 @@ again: raw_inode->i_gid_high = 0; } raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); - raw_inode->i_size = cpu_to_le32(ei->i_disksize); + disksize = cpu_to_le32(ei->i_disksize); + if (disksize != raw_inode->i_size) { + need_datasync = 1; + raw_inode->i_size = disksize; + } raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); @@ -3125,8 +3131,11 @@ again: if (!S_ISREG(inode->i_mode)) { raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); } else { - raw_inode->i_size_high = - cpu_to_le32(ei->i_disksize >> 32); + disksize = cpu_to_le32(ei->i_disksize >> 32); + if (disksize != raw_inode->i_size_high) { + raw_inode->i_size_high = disksize; + need_datasync = 1; + } if (ei->i_disksize > 0x7fffffffULL) { struct super_block *sb = inode->i_sb; if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, @@ -3179,6 +3188,8 @@ again: ext3_clear_inode_state(inode, EXT3_STATE_NEW); atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid); + if (need_datasync) + atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid); out_brelse: brelse (bh); ext3_std_error(inode->i_sb, err); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists