Re: [syzbot] WARNING: lock held when returning to user space in f2fs_ioc_start_atomic_write

From: syzbot
Date: Wed Aug 14 2024 - 14:59:33 EST


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Subject: WARNING: lock held when returning to user space in f2fs_ioc_start_atomic_write
Author: djahchankoike@xxxxxxxxx

#syz test

Reader lock unreleased when returning upon error.

Signed-off-by: Diogo Jahchan Koike <djahchankoike@xxxxxxxxx>
---
fs/f2fs/file.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 270c32e3385f..3ce8478ae5be 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2172,6 +2172,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate)
ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX);
if (ret) {
f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
+ f2fs_up_write(&fi->i_gc_rwsem[READ]);
goto out;
}

@@ -2181,6 +2182,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate)
pinode = f2fs_iget(inode->i_sb, fi->i_pino);
if (IS_ERR(pinode)) {
f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
+ f2fs_up_write(&fi->i_gc_rwsem[READ]);
ret = PTR_ERR(pinode);
goto out;
}
@@ -2189,6 +2191,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate)
iput(pinode);
if (ret) {
f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
+ f2fs_up_write(&fi->i_gc_rwsem[READ]);
goto out;
}

@@ -2202,6 +2205,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate)
ret = f2fs_do_truncate_blocks(fi->cow_inode, 0, true);
if (ret) {
f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
+ f2fs_up_write(&fi->i_gc_rwsem[READ]);
goto out;
}
}
--
2.39.2