From 61fbae2b2b1201525f8f0f35e0bdf6dfa8ec8541 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 24 Feb 2020 19:20:17 +0800 Subject: f2fs: fix to avoid NULL pointer dereference Unable to handle kernel NULL pointer dereference at virtual address 00000000 PC is at f2fs_free_dic+0x60/0x2c8 LR is at f2fs_decompress_pages+0x3c4/0x3e8 f2fs_free_dic+0x60/0x2c8 f2fs_decompress_pages+0x3c4/0x3e8 __read_end_io+0x78/0x19c f2fs_post_read_work+0x6c/0x94 process_one_work+0x210/0x48c worker_thread+0x2e8/0x44c kthread+0x110/0x120 ret_from_fork+0x10/0x18 In f2fs_free_dic(), we can not use f2fs_put_page(,1) to release dic->tpages[i], as the page's mapping is NULL. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/compress.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/f2fs/compress.c') diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c index ef7dd04312fe..dde8ca08e94d 100644 --- a/fs/f2fs/compress.c +++ b/fs/f2fs/compress.c @@ -1137,7 +1137,8 @@ void f2fs_free_dic(struct decompress_io_ctx *dic) for (i = 0; i < dic->cluster_size; i++) { if (dic->rpages[i]) continue; - f2fs_put_page(dic->tpages[i], 1); + unlock_page(dic->tpages[i]); + put_page(dic->tpages[i]); } kfree(dic->tpages); } -- cgit v1.2.3