| Message ID | 20180426112027.11258-2-guaneryu@gmail.com |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | random ext4 ea_inode fixes | expand |
On Thu, Apr 26, 2018 at 07:20:26PM +0800, Eryu Guan wrote: > I hit ENOSPC error when creating new file in a newly created ext4 > with ea_inode feature enabled, if selinux is enabled and ext4 is > mounted without any selinux context. e.g. > > mkfs -t ext4 -O ea_inode -F /dev/sda5 > mount /dev/sda5 /mnt/ext4 > touch /mnt/ext4/testfile # got ENOSPC here > > It turns out that we run out of journal credits in > ext4_xattr_set_handle() when creating new selinux label for the > newly created inode. > > This is because that in __ext4_new_inode() we use > __ext4_xattr_set_credits() to calculate the reserved credits for new > xattr, with the 'is_create' argument being true, which implies less > credits in the ea_inode case. But we calculate the required credits > in ext4_xattr_set_handle() with 'is_create' being false, which means > we need more credits if ea_inode feature is enabled. So we don't > have enough credits and error out with ENOSPC. > > Fix it by simply calling ext4_xattr_set_handle() with XATTR_CREATE > flag in ext4_initxattrs(), so we end up with requiring less credits > than reserved. The semantic of XATTR_CREATE is "Perform a pure > create, which fails if the named attribute exists already." (from > setxattr(2)), which is fine in this case, because we only call > ext4_initxattrs() on newly created inode. > > Fixes: af65207c76ce ("ext4: fix __ext4_new_inode() journal credits calculation") > Cc: Tahsin Erdogan <tahsin@google.com> > Signed-off-by: Eryu Guan <guaneryu@gmail.com> Thanks, applied. - Ted
diff --git a/fs/ext4/xattr_security.c b/fs/ext4/xattr_security.c index 629001b28632..197a9d8a15ef 100644 --- a/fs/ext4/xattr_security.c +++ b/fs/ext4/xattr_security.c @@ -43,7 +43,7 @@ ext4_initxattrs(struct inode *inode, const struct xattr *xattr_array, err = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_SECURITY, xattr->name, xattr->value, - xattr->value_len, 0); + xattr->value_len, XATTR_CREATE); if (err < 0) break; }
I hit ENOSPC error when creating new file in a newly created ext4 with ea_inode feature enabled, if selinux is enabled and ext4 is mounted without any selinux context. e.g. mkfs -t ext4 -O ea_inode -F /dev/sda5 mount /dev/sda5 /mnt/ext4 touch /mnt/ext4/testfile # got ENOSPC here It turns out that we run out of journal credits in ext4_xattr_set_handle() when creating new selinux label for the newly created inode. This is because that in __ext4_new_inode() we use __ext4_xattr_set_credits() to calculate the reserved credits for new xattr, with the 'is_create' argument being true, which implies less credits in the ea_inode case. But we calculate the required credits in ext4_xattr_set_handle() with 'is_create' being false, which means we need more credits if ea_inode feature is enabled. So we don't have enough credits and error out with ENOSPC. Fix it by simply calling ext4_xattr_set_handle() with XATTR_CREATE flag in ext4_initxattrs(), so we end up with requiring less credits than reserved. The semantic of XATTR_CREATE is "Perform a pure create, which fails if the named attribute exists already." (from setxattr(2)), which is fine in this case, because we only call ext4_initxattrs() on newly created inode. Fixes: af65207c76ce ("ext4: fix __ext4_new_inode() journal credits calculation") Cc: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Eryu Guan <guaneryu@gmail.com> --- fs/ext4/xattr_security.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)