6.9-stable review patch. If anyone has any objections, please let me know.
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From: Baokun Li libaokun1@huawei.com
[ Upstream commit 0ece614a52bc9d219b839a6a29282b30d10e0c48 ]
In cachefiles_check_volume_xattr(), the error returned by vfs_getxattr() is not passed to ret, so it ends up returning -ESTALE, which leads to an endless loop as follows:
cachefiles_acquire_volume retry: ret = cachefiles_check_volume_xattr ret = -ESTALE xlen = vfs_getxattr // return -EIO // The ret is not updated when xlen < 0, so -ESTALE is returned. return ret // Supposed to jump out of the loop at this judgement. if (ret != -ESTALE) goto error_dir; cachefiles_bury_object // EIO causes rename failure goto retry;
Hence propagate the error returned by vfs_getxattr() to avoid the above issue. Do the same in cachefiles_check_auxdata().
Fixes: 32e150037dce ("fscache, cachefiles: Store the volume coherency data") Fixes: 72b957856b0c ("cachefiles: Implement metadata/coherency data storage in xattrs") Signed-off-by: Baokun Li libaokun1@huawei.com Link: https://lore.kernel.org/r/20240628062930.2467993-5-libaokun@huaweicloud.com Reviewed-by: Gao Xiang hsiangkao@linux.alibaba.com Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/cachefiles/xattr.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c index bcb6173943ee4..4dd8a993c60a8 100644 --- a/fs/cachefiles/xattr.c +++ b/fs/cachefiles/xattr.c @@ -110,9 +110,11 @@ int cachefiles_check_auxdata(struct cachefiles_object *object, struct file *file if (xlen == 0) xlen = vfs_getxattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache, buf, tlen); if (xlen != tlen) { - if (xlen < 0) + if (xlen < 0) { + ret = xlen; trace_cachefiles_vfs_error(object, file_inode(file), xlen, cachefiles_trace_getxattr_error); + } if (xlen == -EIO) cachefiles_io_error_obj( object, @@ -252,6 +254,7 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume) xlen = vfs_getxattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache, buf, len); if (xlen != len) { if (xlen < 0) { + ret = xlen; trace_cachefiles_vfs_error(NULL, d_inode(dentry), xlen, cachefiles_trace_getxattr_error); if (xlen == -EIO)