From 0b5bbeee4de616a268db77e2f40f19ab010a367b Mon Sep 17 00:00:00 2001 From: Hao Ge Date: Wed, 6 Nov 2024 16:28:41 +0800 Subject: [PATCH] isofs: avoid memory leak in iocharset A memleak was found as below: unreferenced object 0xffff0000d10164d8 (size 8): comm "pool-udisksd", pid 108217, jiffies 4295408555 hex dump (first 8 bytes): 75 74 66 38 00 cc cc cc utf8.... backtrace (crc de430d31): [] kmemleak_alloc+0xb8/0xc8 [] __kmalloc_node_track_caller_noprof+0x380/0x474 [] kstrdup+0x70/0xfc [] isofs_parse_param+0x228/0x2c0 [isofs] [] vfs_parse_fs_param+0xf4/0x164 [] vfs_parse_fs_string+0x8c/0xd4 [] vfs_parse_monolithic_sep+0xb0/0xfc [] generic_parse_monolithic+0x30/0x3c [] parse_monolithic_mount_data+0x40/0x4c [] path_mount+0x6c4/0x9ec [] do_mount+0xac/0xc4 [] __arm64_sys_mount+0x16c/0x2b0 [] invoke_syscall+0x7c/0x104 [] el0_svc_common.constprop.1+0xe0/0x104 [] do_el0_svc+0x2c/0x38 [] el0_svc+0x3c/0x1b8 The opt->iocharset is freed inside the isofs_fill_super function, But there may be situations where it's not possible to enter this function. For example, in the get_tree_bdev_flags function,when encountering the situation where "Can't mount, would change RO state," In such a case, isofs_fill_super will not have the opportunity to be called,which means that opt->iocharset will not have the chance to be freed,ultimately leading to a memory leak. Let's move the memory freeing of opt->iocharset into isofs_free_fc function. Fixes: 1b17a46c9243 ("isofs: convert isofs to use the new mount API") Signed-off-by: Hao Ge Reviewed-by: Eric Sandeen Signed-off-by: Jan Kara Link: https://patch.msgid.link/20241106082841.51773-1-hao.ge@linux.dev --- fs/isofs/inode.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c index f50311a6b429..47038e660812 100644 --- a/fs/isofs/inode.c +++ b/fs/isofs/inode.c @@ -948,8 +948,6 @@ static int isofs_fill_super(struct super_block *s, struct fs_context *fc) goto out_no_inode; } - kfree(opt->iocharset); - return 0; /* @@ -987,7 +985,6 @@ static int isofs_fill_super(struct super_block *s, struct fs_context *fc) brelse(bh); brelse(pri_bh); out_freesbi: - kfree(opt->iocharset); kfree(sbi); s->s_fs_info = NULL; return error; @@ -1528,7 +1525,10 @@ static int isofs_get_tree(struct fs_context *fc) static void isofs_free_fc(struct fs_context *fc) { - kfree(fc->fs_private); + struct isofs_options *opt = fc->fs_private; + + kfree(opt->iocharset); + kfree(opt); } static const struct fs_context_operations isofs_context_ops = {