6.10-stable review patch. If anyone has any objections, please let me know.
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From: Jan Kara jack@suse.cz
[ Upstream commit 8832fc1e502687869606bb0a7b79848ed3bf036f ]
udf_evict_inode() calls udf_setsize() to truncate deleted inode. However inode deletion through udf_evict_inode() can happen from inode reclaim context and udf_setsize() grabs mapping->invalidate_lock which isn't generally safe to acquire from fs reclaim context since we allocate pages under mapping->invalidate_lock for example in a page fault path. This is however not a real deadlock possibility as by the time udf_evict_inode() is called, nobody can be accessing the inode, even less work with its page cache. So this is just a lockdep triggering false positive. Fix the problem by moving mapping->invalidate_lock locking outsize of udf_setsize() into udf_setattr() as grabbing mapping->invalidate_lock from udf_evict_inode() is pointless.
Reported-by: syzbot+0333a6f4b88bcd68a62f@syzkaller.appspotmail.com Fixes: b9a861fd527a ("udf: Protect truncate and file type conversion with invalidate_lock") Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Sasha Levin sashal@kernel.org --- fs/udf/file.c | 2 ++ fs/udf/inode.c | 11 ++++------- 2 files changed, 6 insertions(+), 7 deletions(-)
diff --git a/fs/udf/file.c b/fs/udf/file.c index 97c59585208ca..3a4179de316b4 100644 --- a/fs/udf/file.c +++ b/fs/udf/file.c @@ -232,7 +232,9 @@ static int udf_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size != i_size_read(inode)) { + filemap_invalidate_lock(inode->i_mapping); error = udf_setsize(inode, attr->ia_size); + filemap_invalidate_unlock(inode->i_mapping); if (error) return error; } diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 2fb21c5ffccfe..08767bd21eb7f 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -1250,7 +1250,6 @@ int udf_setsize(struct inode *inode, loff_t newsize) if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) return -EPERM;
- filemap_invalidate_lock(inode->i_mapping); iinfo = UDF_I(inode); if (newsize > inode->i_size) { if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { @@ -1263,11 +1262,11 @@ int udf_setsize(struct inode *inode, loff_t newsize) } err = udf_expand_file_adinicb(inode); if (err) - goto out_unlock; + return err; } err = udf_extend_file(inode, newsize); if (err) - goto out_unlock; + return err; set_size: truncate_setsize(inode, newsize); } else { @@ -1285,14 +1284,14 @@ int udf_setsize(struct inode *inode, loff_t newsize) err = block_truncate_page(inode->i_mapping, newsize, udf_get_block); if (err) - goto out_unlock; + return err; truncate_setsize(inode, newsize); down_write(&iinfo->i_data_sem); udf_clear_extent_cache(inode); err = udf_truncate_extents(inode); up_write(&iinfo->i_data_sem); if (err) - goto out_unlock; + return err; } update_time: inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); @@ -1300,8 +1299,6 @@ int udf_setsize(struct inode *inode, loff_t newsize) udf_sync_inode(inode); else mark_inode_dirty(inode); -out_unlock: - filemap_invalidate_unlock(inode->i_mapping); return err; }