> On Tue, Jun 02, 2020 at 01:03:05PM +0800, butt3rflyh4ck wrote: > > I report a bug (in linux-5.7.0-rc7) found by syzkaller. > > > > kernel config: > > https://protect2.fireeye.com/url?k=f3a88a7d-ae6446d8-f3a90132-0cc47a30 > > d446-6021a2fbdd1681a8&q=1&u=https%3A%2F%2Fgithub.com%2Fbutterflyhack%2 > > Fsyzkaller-fuzz%2Fblob%2Fmaster%2Fconfig-v5.7.0-rc7 > > > > and can reproduce. > > > > A param->string held by exfat_mount_options. > > Humm... > > First of all, exfat_free() ought to call exfat_free_upcase_table(). > What's more, WTF bother with that kstrdup(), anyway? Just steal the string and be done with that... Thanks for your patch. I will push it to exfat tree. > > Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > --- > diff --git a/fs/exfat/super.c b/fs/exfat/super.c index 0565d5539d57..01cd7ed1614d 100644 > --- a/fs/exfat/super.c > +++ b/fs/exfat/super.c > @@ -259,9 +259,8 @@ static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param) > break; > case Opt_charset: > exfat_free_iocharset(sbi); > - opts->iocharset = kstrdup(param->string, GFP_KERNEL); > - if (!opts->iocharset) > - return -ENOMEM; > + opts->iocharset = param->string; > + param->string = NULL; > break; > case Opt_errors: > opts->errors = result.uint_32; > @@ -611,7 +610,10 @@ static int exfat_get_tree(struct fs_context *fc) > > static void exfat_free(struct fs_context *fc) { > - kfree(fc->s_fs_info); > + struct exfat_sb_info *sbi = fc->s_fs_info; > + > + exfat_free_iocharset(sbi); > + kfree(sbi); > } > > static const struct fs_context_operations exfat_context_ops = {
