From: Zhihao Cheng chengzhihao1@huawei.com
[ Upstream commit a0c51565730729f0df2ee886e34b4da6d359a10b ]
Following process: vfs_setxattr(host) ubifs_xattr_set down_write(host_ui->xattr_sem) <- lock first time create_xattr ubifs_new_inode(host) fscrypt_prepare_new_inode(host) fscrypt_policy_to_inherit(host) if (IS_ENCRYPTED(inode)) fscrypt_require_key(host) fscrypt_get_encryption_info(host) ubifs_xattr_get(host) down_read(host_ui->xattr_sem) <- AA deadlock
, which may trigger an AA deadlock problem:
[ 102.620871] INFO: task setfattr:1599 blocked for more than 10 seconds. [ 102.625298] Not tainted 5.19.0-rc7-00001-gb666b6823ce0-dirty #711 [ 102.628732] task:setfattr state:D stack: 0 pid: 1599 [ 102.628749] Call Trace: [ 102.628753] <TASK> [ 102.628776] __schedule+0x482/0x1060 [ 102.629964] schedule+0x92/0x1a0 [ 102.629976] rwsem_down_read_slowpath+0x287/0x8c0 [ 102.629996] down_read+0x84/0x170 [ 102.630585] ubifs_xattr_get+0xd1/0x370 [ubifs] [ 102.630730] ubifs_crypt_get_context+0x1f/0x30 [ubifs] [ 102.630791] fscrypt_get_encryption_info+0x7d/0x1c0 [ 102.630810] fscrypt_policy_to_inherit+0x56/0xc0 [ 102.630817] fscrypt_prepare_new_inode+0x35/0x160 [ 102.630830] ubifs_new_inode+0xcc/0x4b0 [ubifs] [ 102.630873] ubifs_xattr_set+0x591/0x9f0 [ubifs] [ 102.630961] xattr_set+0x8c/0x3e0 [ubifs] [ 102.631003] __vfs_setxattr+0x71/0xc0 [ 102.631026] vfs_setxattr+0x105/0x270 [ 102.631034] do_setxattr+0x6d/0x110 [ 102.631041] setxattr+0xa0/0xd0 [ 102.631087] __x64_sys_setxattr+0x2f/0x40
Fetch a reproducer in [Link].
Just like ext4 does, which skips encrypting for inode with EXT4_EA_INODE_FL flag. Stop encypting xattr inode for ubifs.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216260 Fixes: f4e3634a3b64222 ("ubifs: Fix races between xattr_{set|get} ...") Fixes: d475a507457b5ca ("ubifs: Add skeleton for fscrypto") Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Signed-off-by: Richard Weinberger richard@nod.at Stable-dep-of: 3a36d20e0129 ("ubifs: Fix memory leak in do_rename") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ubifs/dir.c | 25 ++++++++++++++----------- fs/ubifs/ubifs.h | 2 +- fs/ubifs/xattr.c | 2 +- 3 files changed, 16 insertions(+), 13 deletions(-)
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c index 7717d23906dbe..005566bc6dc13 100644 --- a/fs/ubifs/dir.c +++ b/fs/ubifs/dir.c @@ -68,13 +68,14 @@ static int inherit_flags(const struct inode *dir, umode_t mode) * @c: UBIFS file-system description object * @dir: parent directory inode * @mode: inode mode flags + * @is_xattr: whether the inode is xattr inode * * This function finds an unused inode number, allocates new inode and * initializes it. Returns new inode in case of success and an error code in * case of failure. */ struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir, - umode_t mode) + umode_t mode, bool is_xattr) { int err; struct inode *inode; @@ -99,10 +100,12 @@ struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir, current_time(inode); inode->i_mapping->nrpages = 0;
- err = fscrypt_prepare_new_inode(dir, inode, &encrypted); - if (err) { - ubifs_err(c, "fscrypt_prepare_new_inode failed: %i", err); - goto out_iput; + if (!is_xattr) { + err = fscrypt_prepare_new_inode(dir, inode, &encrypted); + if (err) { + ubifs_err(c, "fscrypt_prepare_new_inode failed: %i", err); + goto out_iput; + } }
switch (mode & S_IFMT) { @@ -309,7 +312,7 @@ static int ubifs_create(struct user_namespace *mnt_userns, struct inode *dir,
sz_change = CALC_DENT_SIZE(fname_len(&nm));
- inode = ubifs_new_inode(c, dir, mode); + inode = ubifs_new_inode(c, dir, mode, false); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_fname; @@ -370,7 +373,7 @@ static struct inode *create_whiteout(struct inode *dir, struct dentry *dentry) if (err) return ERR_PTR(err);
- inode = ubifs_new_inode(c, dir, mode); + inode = ubifs_new_inode(c, dir, mode, false); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_free; @@ -462,7 +465,7 @@ static int ubifs_tmpfile(struct user_namespace *mnt_userns, struct inode *dir, return err; }
- inode = ubifs_new_inode(c, dir, mode); + inode = ubifs_new_inode(c, dir, mode, false); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_budg; @@ -1005,7 +1008,7 @@ static int ubifs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
sz_change = CALC_DENT_SIZE(fname_len(&nm));
- inode = ubifs_new_inode(c, dir, S_IFDIR | mode); + inode = ubifs_new_inode(c, dir, S_IFDIR | mode, false); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_fname; @@ -1092,7 +1095,7 @@ static int ubifs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
sz_change = CALC_DENT_SIZE(fname_len(&nm));
- inode = ubifs_new_inode(c, dir, mode); + inode = ubifs_new_inode(c, dir, mode, false); if (IS_ERR(inode)) { kfree(dev); err = PTR_ERR(inode); @@ -1174,7 +1177,7 @@ static int ubifs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
sz_change = CALC_DENT_SIZE(fname_len(&nm));
- inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO); + inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO, false); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_fname; diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h index efbb4554a4a6f..398551bef5986 100644 --- a/fs/ubifs/ubifs.h +++ b/fs/ubifs/ubifs.h @@ -2002,7 +2002,7 @@ int ubifs_update_time(struct inode *inode, struct timespec64 *time, int flags);
/* dir.c */ struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir, - umode_t mode); + umode_t mode, bool is_xattr); int ubifs_getattr(struct user_namespace *mnt_userns, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags); int ubifs_check_dir_empty(struct inode *dir); diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c index e4f193eae4b2b..9ff2614bdeca0 100644 --- a/fs/ubifs/xattr.c +++ b/fs/ubifs/xattr.c @@ -110,7 +110,7 @@ static int create_xattr(struct ubifs_info *c, struct inode *host, if (err) return err;
- inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO); + inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO, true); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_budg;