diff options
author | Trond Myklebust <trondmy@gmail.com> | 2020-02-02 17:53:53 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-11 04:35:32 -0800 |
commit | 293cdcd89b6c57540449a55c9baccf71321f3f0d (patch) | |
tree | 0acfcddbda889fb6529126aea981fd7d71f0adc7 /fs | |
parent | 8d313c04b425e990f600a232f19f1557016648c1 (diff) |
NFS: Fix memory leaks and corruption in readdir
commit 4b310319c6a8ce708f1033d57145e2aa027a883c upstream.
nfs_readdir_xdr_to_array() must not exit without having initialised
the array, so that the page cache deletion routines can safely
call nfs_readdir_clear_array().
Furthermore, we should ensure that if we exit nfs_readdir_filler()
with an error, we free up any page contents to prevent a leak
if we try to fill the page again.
Fixes: 11de3b11e08c ("NFS: Fix a memory leak in nfs_readdir")
Cc: stable@vger.kernel.org # v2.6.37+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/nfs/dir.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index e180033e35cf..54337d8e1738 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -162,6 +162,17 @@ typedef struct { bool eof; } nfs_readdir_descriptor_t; +static +void nfs_readdir_init_array(struct page *page) +{ + struct nfs_cache_array *array; + + array = kmap_atomic(page); + memset(array, 0, sizeof(struct nfs_cache_array)); + array->eof_index = -1; + kunmap_atomic(array); +} + /* * we are freeing strings created by nfs_add_to_readdir_array() */ @@ -174,6 +185,7 @@ void nfs_readdir_clear_array(struct page *page) array = kmap_atomic(page); for (i = 0; i < array->size; i++) kfree(array->array[i].string.name); + array->size = 0; kunmap_atomic(array); } @@ -610,6 +622,8 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, int status = -ENOMEM; unsigned int array_size = ARRAY_SIZE(pages); + nfs_readdir_init_array(page); + entry.prev_cookie = 0; entry.cookie = desc->last_cookie; entry.eof = 0; @@ -626,8 +640,6 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, } array = kmap(page); - memset(array, 0, sizeof(struct nfs_cache_array)); - array->eof_index = -1; status = nfs_readdir_alloc_pages(pages, array_size); if (status < 0) @@ -682,6 +694,7 @@ int nfs_readdir_filler(void *data, struct page* page) unlock_page(page); return 0; error: + nfs_readdir_clear_array(page); unlock_page(page); return ret; } |