f2fs: correct removexattr behavior for null valued extended attribute

PATCH In review Chao Yu 2 participants 2 messages Jan 20, 2018 F2FS file system

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Chao Yu

author maintainer

2018-01-20 07:46 UTC #0 lore raw

PATCH 1/1 f2fs: correct removexattr behavior for null valued extended attribute

From: Daeho Jeong <[email protected]>

__vfs_removexattr() transfers "NULL" value to the setxattr handler of the f2fs filesystem in order to remove the extended attribute. But, __f2fs_setxattr() just ignores the removal request when the value of the extended attribute is already NULL. We have to remove the extended attribute itself even if the value of that is already NULL.

We can reporduce this bug with the below:

1. touch file
2. setfattr -n "user.foo" file
3. setfattr -x "user.foo" file
4. getfattr -d file

Quoted 1 line

user.foo

Signed-off-by Daeho Jeong <[email protected]>

Signed-off-by Youngjin Gil <[email protected]>

Tested-by Hobin Woo <[email protected]>

Tested-by Chao Yu <[email protected]>

Reviewed-by Chao Yu <[email protected]>

Signed-off-by Chao Yu <[email protected]>

---
 fs/f2fs/xattr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

fs/f2fs/xattr.c +1 -1

index 600162f4ddbf..ae2dfa709f5d 100644
@@ -600,7 +600,7 @@ static int __f2fs_setxattr(struct inode *inode, int index,
 			goto exit;
 		}
 
-		if (f2fs_xattr_value_same(here, value, size))
+		if (value && f2fs_xattr_value_same(here, value, size))
 			goto exit;
 	} else if ((flags & XATTR_REPLACE)) {
 		error = -ENODATA;

Signature · 6 lines

2.14.1.145.gb3622a4ee


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Jaegeuk Kim

maintainer

2018-01-20 22:04 UTC #1 lore raw

Thanks,

Quoted 41 lines · Chao Yu

From: Daeho Jeong <[email protected]>
__vfs_removexattr() transfers "NULL" value to the setxattr handler of the f2fs filesystem in order to remove the extended attribute. But, __f2fs_setxattr() just ignores the removal request when the value of the extended attribute is already NULL. We have to remove the extended attribute itself even if the value of that is already NULL.
We can reporduce this bug with the below:
1. touch file
2. setfattr -n "user.foo" file
3. setfattr -x "user.foo" file
4. getfattr -d file
Quoted 1 line
user.foo
Signed-off-by Daeho Jeong <[email protected]>
Signed-off-by Youngjin Gil <[email protected]>
Tested-by Hobin Woo <[email protected]>
Tested-by Chao Yu <[email protected]>
Reviewed-by Chao Yu <[email protected]>
Signed-off-by Chao Yu <[email protected]>
---
 fs/f2fs/xattr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
fs/f2fs/xattr.c +1 -1
index 600162f4ddbf..ae2dfa709f5d 100644
@@ -600,7 +600,7 @@ static int __f2fs_setxattr(struct inode *inode, int index,
 			goto exit;
 		}
 
-		if (f2fs_xattr_value_same(here, value, size))
+		if (value && f2fs_xattr_value_same(here, value, size))
 			goto exit;
 	} else if ((flags & XATTR_REPLACE)) {
 		error = -ENODATA;
Signature · 1 line
2.14.1.145.gb3622a4ee

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