From 74983ac20aeafc88d9ceed64a8bf2a9024c488d5 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 25 Mar 2019 16:38:31 +0000 Subject: [PATCH] vfs: Make fs_parse() handle fs_param_is_fd-type params better Make fs_parse() handle fs_param_is_fd-type parameters that are passed a string by converting it to an integer (in addition to handling direct fd specification). Also range check the integer. [fix from Yin Fengwei folded] Signed-off-by: David Howells Signed-off-by: Al Viro --- fs/fs_parser.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/fs/fs_parser.c b/fs/fs_parser.c index 460ea4206fa2..d1930adce68d 100644 --- a/fs/fs_parser.c +++ b/fs/fs_parser.c @@ -204,9 +204,23 @@ int fs_parse(struct fs_context *fc, goto okay; case fs_param_is_fd: { - if (param->type != fs_value_is_file) + switch (param->type) { + case fs_value_is_string: + if (!result->has_value) + goto bad_value; + + ret = kstrtouint(param->string, 0, &result->uint_32); + break; + case fs_value_is_file: + result->uint_32 = param->dirfd; + ret = 0; + default: goto bad_value; - goto okay; + } + + if (result->uint_32 > INT_MAX) + goto bad_value; + goto maybe_okay; } case fs_param_is_blockdev: