From: David Howells Date: Sun, 12 May 2019 07:31:23 +0000 (+0100) Subject: afs: Fix afs_xattr_get_yfs() to not try freeing an error value X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=773e0c40253443e0ce5491cb0e414b62f7cc45ed;p=openwrt%2Fstaging%2Fblogic.git afs: Fix afs_xattr_get_yfs() to not try freeing an error value afs_xattr_get_yfs() tries to free yacl, which may hold an error value (say if yfs_fs_fetch_opaque_acl() failed and returned an error). Fix this by allocating yacl up front (since it's a fixed-length struct, unlike afs_acl) and passing it in to the RPC function. This also allows the flags to be placed in the object rather than passing them through to the RPC function. Fixes: ae46578b963f ("afs: Get YFS ACLs and information through xattrs") Signed-off-by: David Howells --- diff --git a/fs/afs/internal.h b/fs/afs/internal.h index b3cd6e8ad59d..74ee0f8ef8dd 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -1382,7 +1382,7 @@ struct yfs_acl { }; extern void yfs_free_opaque_acl(struct yfs_acl *); -extern struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *, unsigned int); +extern struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *, struct yfs_acl *); extern int yfs_fs_store_opaque_acl2(struct afs_fs_cursor *, const struct afs_acl *); /* diff --git a/fs/afs/xattr.c b/fs/afs/xattr.c index b6c44e75b361..d12bcda911e1 100644 --- a/fs/afs/xattr.c +++ b/fs/afs/xattr.c @@ -148,9 +148,8 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, struct afs_vnode *vnode = AFS_FS_I(inode); struct yfs_acl *yacl = NULL; struct key *key; - unsigned int flags = 0; char buf[16], *data; - int which = 0, dsize, ret; + int which = 0, dsize, ret = -ENOMEM; if (strcmp(name, "acl") == 0) which = 0; @@ -163,20 +162,26 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, else return -EOPNOTSUPP; + yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL); + if (!yacl) + goto error; + if (which == 0) - flags |= YFS_ACL_WANT_ACL; + yacl->flags |= YFS_ACL_WANT_ACL; else if (which == 3) - flags |= YFS_ACL_WANT_VOL_ACL; + yacl->flags |= YFS_ACL_WANT_VOL_ACL; key = afs_request_key(vnode->volume->cell); - if (IS_ERR(key)) - return PTR_ERR(key); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error_yacl; + } ret = -ERESTARTSYS; if (afs_begin_vnode_operation(&fc, vnode, key)) { while (afs_select_fileserver(&fc)) { fc.cb_break = afs_calc_vnode_cb_break(vnode); - yacl = yfs_fs_fetch_opaque_acl(&fc, flags); + yfs_fs_fetch_opaque_acl(&fc, yacl); } afs_check_for_remote_deletion(&fc, fc.vnode); @@ -184,44 +189,45 @@ static int afs_xattr_get_yfs(const struct xattr_handler *handler, ret = afs_end_vnode_operation(&fc); } - if (ret == 0) { - switch (which) { - case 0: - data = yacl->acl->data; - dsize = yacl->acl->size; - break; - case 1: - data = buf; - dsize = snprintf(buf, sizeof(buf), "%u", - yacl->inherit_flag); - break; - case 2: - data = buf; - dsize = snprintf(buf, sizeof(buf), "%u", - yacl->num_cleaned); - break; - case 3: - data = yacl->vol_acl->data; - dsize = yacl->vol_acl->size; - break; - default: - ret = -EOPNOTSUPP; - goto out; - } + if (ret < 0) + goto error_key; + + switch (which) { + case 0: + data = yacl->acl->data; + dsize = yacl->acl->size; + break; + case 1: + data = buf; + dsize = snprintf(buf, sizeof(buf), "%u", yacl->inherit_flag); + break; + case 2: + data = buf; + dsize = snprintf(buf, sizeof(buf), "%u", yacl->num_cleaned); + break; + case 3: + data = yacl->vol_acl->data; + dsize = yacl->vol_acl->size; + break; + default: + ret = -EOPNOTSUPP; + goto error_key; + } - ret = dsize; - if (size > 0) { - if (dsize > size) { - ret = -ERANGE; - goto out; - } - memcpy(buffer, data, dsize); + ret = dsize; + if (size > 0) { + if (dsize > size) { + ret = -ERANGE; + goto error_key; } + memcpy(buffer, data, dsize); } -out: - yfs_free_opaque_acl(yacl); +error_key: key_put(key); +error_yacl: + yfs_free_opaque_acl(yacl); +error: return ret; } diff --git a/fs/afs/yfsclient.c b/fs/afs/yfsclient.c index 6cf7d161baa1..d3e9e3fe0b58 100644 --- a/fs/afs/yfsclient.c +++ b/fs/afs/yfsclient.c @@ -2333,12 +2333,6 @@ void yfs_free_opaque_acl(struct yfs_acl *yacl) } } -static void yfs_destroy_fs_fetch_opaque_acl(struct afs_call *call) -{ - yfs_free_opaque_acl(call->reply[0]); - afs_flat_call_destructor(call); -} - /* * YFS.FetchOpaqueACL operation type */ @@ -2346,18 +2340,17 @@ static const struct afs_call_type yfs_RXYFSFetchOpaqueACL = { .name = "YFS.FetchOpaqueACL", .op = yfs_FS_FetchOpaqueACL, .deliver = yfs_deliver_fs_fetch_opaque_acl, - .destructor = yfs_destroy_fs_fetch_opaque_acl, + .destructor = afs_flat_call_destructor, }; /* * Fetch the YFS advanced ACLs for a file. */ struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *fc, - unsigned int flags) + struct yfs_acl *yacl) { struct afs_vnode *vnode = fc->vnode; struct afs_call *call; - struct yfs_acl *yacl; struct afs_net *net = afs_v2net(vnode); __be32 *bp; @@ -2370,19 +2363,15 @@ struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *fc, sizeof(__be32) * 2 + sizeof(struct yfs_xdr_YFSFetchStatus) + sizeof(struct yfs_xdr_YFSVolSync)); - if (!call) - goto nomem; - - yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL); - if (!yacl) - goto nomem_call; + if (!call) { + fc->ac.error = -ENOMEM; + return ERR_PTR(-ENOMEM); + } - yacl->flags = flags; call->key = fc->key; call->reply[0] = yacl; call->reply[1] = vnode; call->reply[2] = NULL; /* volsync */ - call->ret_reply0 = true; /* marshall the parameters */ bp = call->request; @@ -2396,12 +2385,6 @@ struct yfs_acl *yfs_fs_fetch_opaque_acl(struct afs_fs_cursor *fc, trace_afs_make_fs_call(call, &vnode->fid); afs_make_call(&fc->ac, call, GFP_KERNEL); return (struct yfs_acl *)afs_wait_for_call_to_complete(call, &fc->ac); - -nomem_call: - afs_put_call(call); -nomem: - fc->ac.error = -ENOMEM; - return ERR_PTR(-ENOMEM); } /*