From: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Subject: ocfs2: fix crash when mount with quota enabled There is a reported crash when mounting ocfs2 with quota enabled. RIP: 0010:ocfs2_qinfo_lock_res_init+0x44/0x50 [ocfs2] Call Trace: <TASK> ocfs2_local_read_info+0xb9/0x6f0 [ocfs2] ? ocfs2_local_check_quota_file+0x197/0x390 [ocfs2] dquot_load_quota_sb+0x216/0x470 ? preempt_count_add+0x68/0xa0 dquot_load_quota_inode+0x85/0x100 ocfs2_enable_quotas+0xa0/0x1c0 [ocfs2] ocfs2_fill_super.cold+0xc8/0x1bf [ocfs2] mount_bdev+0x185/0x1b0 ? ocfs2_initialize_super.isra.0+0xf40/0xf40 [ocfs2] legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 path_mount+0x465/0xac0 __x64_sys_mount+0x103/0x140 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae </TASK> It is caused by when initializing dqi_gqlock, the corresponding dqi_type and dqi_sb are not properly initialized. This issue is introduced by commit 6c85c2c72819, which wants to avoid accessing uninitialized variables in error cases. So make global quota info properly initialized. Link: https://lkml.kernel.org/r/20220323023644.40084-1-joseph.qi@xxxxxxxxxxxxxxxxx Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1007141 Fixes: 6c85c2c72819 ("ocfs2: quota_local: fix possible uninitialized-variable access in ocfs2_local_read_info()") Signed-off-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Reported-by: Dayvison <sathlerds@xxxxxxxxx> Tested-by: Valentin Vidic <vvidic@xxxxxxxxxxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/ocfs2/quota_global.c | 23 ++++++++++++----------- fs/ocfs2/quota_local.c | 2 -- 2 files changed, 12 insertions(+), 13 deletions(-) --- a/fs/ocfs2/quota_global.c~ocfs2-fix-crash-when-mount-with-quota-enabled +++ a/fs/ocfs2/quota_global.c @@ -337,7 +337,6 @@ void ocfs2_unlock_global_qf(struct ocfs2 /* Read information header from global quota file */ int ocfs2_global_read_info(struct super_block *sb, int type) { - struct inode *gqinode = NULL; unsigned int ino[OCFS2_MAXQUOTAS] = { USER_QUOTA_SYSTEM_INODE, GROUP_QUOTA_SYSTEM_INODE }; struct ocfs2_global_disk_dqinfo dinfo; @@ -346,29 +345,31 @@ int ocfs2_global_read_info(struct super_ u64 pcount; int status; + oinfo->dqi_gi.dqi_sb = sb; + oinfo->dqi_gi.dqi_type = type; + ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo); + oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk); + oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops; + oinfo->dqi_gqi_bh = NULL; + oinfo->dqi_gqi_count = 0; + /* Read global header */ - gqinode = ocfs2_get_system_file_inode(OCFS2_SB(sb), ino[type], + oinfo->dqi_gqinode = ocfs2_get_system_file_inode(OCFS2_SB(sb), ino[type], OCFS2_INVALID_SLOT); - if (!gqinode) { + if (!oinfo->dqi_gqinode) { mlog(ML_ERROR, "failed to get global quota inode (type=%d)\n", type); status = -EINVAL; goto out_err; } - oinfo->dqi_gi.dqi_sb = sb; - oinfo->dqi_gi.dqi_type = type; - oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk); - oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops; - oinfo->dqi_gqi_bh = NULL; - oinfo->dqi_gqi_count = 0; - oinfo->dqi_gqinode = gqinode; + status = ocfs2_lock_global_qf(oinfo, 0); if (status < 0) { mlog_errno(status); goto out_err; } - status = ocfs2_extent_map_get_blocks(gqinode, 0, &oinfo->dqi_giblk, + status = ocfs2_extent_map_get_blocks(oinfo->dqi_gqinode, 0, &oinfo->dqi_giblk, &pcount, NULL); if (status < 0) goto out_unlock; --- a/fs/ocfs2/quota_local.c~ocfs2-fix-crash-when-mount-with-quota-enabled +++ a/fs/ocfs2/quota_local.c @@ -702,8 +702,6 @@ static int ocfs2_local_read_info(struct info->dqi_priv = oinfo; oinfo->dqi_type = type; INIT_LIST_HEAD(&oinfo->dqi_chunk); - oinfo->dqi_gqinode = NULL; - ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo); oinfo->dqi_rec = NULL; oinfo->dqi_lqi_bh = NULL; oinfo->dqi_libh = NULL; _
