diff options
| author | Trond Myklebust <trondmy@gmail.com> | 2020-02-02 17:53:53 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-14 16:31:07 -0500 |
| commit | 67a56e9743171bdacddbdc05a58735aa024bb474 (patch) | |
| tree | cfe5eac32b1496e6bc1c6f874f772bf383380fc7 | |
| parent | 9dc9bee77805acd813f42b6aa996054d2f939a72 (diff) | |
NFS: Fix memory leaks and corruption in readdir
[ Upstream commit 4b310319c6a8ce708f1033d57145e2aa027a883c ]
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: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/nfs/dir.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index a41df7d44bd7..5936c54ac5fd 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -169,6 +169,17 @@ typedef struct { unsigned int eof:1; } 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); +} + /* * The caller is responsible for calling nfs_readdir_release_array(page) */ @@ -202,6 +213,7 @@ 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); } @@ -643,6 +655,8 @@ 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; @@ -663,8 +677,8 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, status = PTR_ERR(array); goto out_label_free; } - memset(array, 0, sizeof(struct nfs_cache_array)); - array->eof_index = -1; + + array = kmap(page); status = nfs_readdir_alloc_pages(pages, array_size); if (status < 0) @@ -719,6 +733,7 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page) unlock_page(page); return 0; error: + nfs_readdir_clear_array(page); unlock_page(page); return ret; } |