From 4153d789e299b29cbc57276d687c92f3a098e59b Mon Sep 17 00:00:00 2001 From: Zhang Xiaoxu Date: Sat, 22 Oct 2022 15:35:21 +0800 Subject: cifs: Fix pages array leak when writedata alloc failed in cifs_writedata_alloc() There is a memory leak when writedata alloc failed: unreferenced object 0xffff888192364000 (size 8192): comm "sync", pid 22839, jiffies 4297313967 (age 60.230s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000027de0814>] __kmalloc+0x4d/0x150 [<00000000b21e81ab>] cifs_writepages+0x35f/0x14a0 [<0000000076f7d20e>] do_writepages+0x10a/0x360 [<00000000d6a36edc>] filemap_fdatawrite_wbc+0x95/0xc0 [<000000005751a323>] __filemap_fdatawrite_range+0xa7/0xe0 [<0000000088afb0ca>] file_write_and_wait_range+0x66/0xb0 [<0000000063dbc443>] cifs_strict_fsync+0x80/0x5f0 [<00000000c4624754>] __x64_sys_fsync+0x40/0x70 [<000000002c0dc744>] do_syscall_64+0x35/0x80 [<0000000052f46bee>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 cifs_writepages+0x35f/0x14a0 is: kmalloc_array at include/linux/slab.h:628 (inlined by) kcalloc at include/linux/slab.h:659 (inlined by) cifs_writedata_alloc at fs/cifs/file.c:2438 (inlined by) wdata_alloc_and_fillpages at fs/cifs/file.c:2527 (inlined by) cifs_writepages at fs/cifs/file.c:2705 If writedata alloc failed in cifs_writedata_alloc(), the pages array should be freed. Fixes: 8e7360f67e75 ("CIFS: Add support for direct pages in wdata") Signed-off-by: Zhang Xiaoxu Reviewed-by: Paulo Alcantara (SUSE) Signed-off-by: Steve French --- fs/cifs/file.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 5b3b308e115c..d9fbf1ec6029 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2434,12 +2434,16 @@ cifs_writev_complete(struct work_struct *work) struct cifs_writedata * cifs_writedata_alloc(unsigned int nr_pages, work_func_t complete) { + struct cifs_writedata *writedata = NULL; struct page **pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); - if (pages) - return cifs_writedata_direct_alloc(pages, complete); + if (pages) { + writedata = cifs_writedata_direct_alloc(pages, complete); + if (!writedata) + kvfree(pages); + } - return NULL; + return writedata; } struct cifs_writedata * -- cgit v1.2.3-59-g8ed1b