gfs2: Switch from strlcpy to strscpy

commit 204c0300c4 upstream.

Switch from strlcpy to strscpy and make sure that @count is the size of
the smaller of the source and destination buffers.  This prevents
reading beyond the end of the source buffer when the source string isn't
null terminated.

Found by a modified version of syzkaller.

Suggested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andreas Gruenbacher 2022-08-26 15:12:17 +02:00 committed by Greg Kroah-Hartman
parent 8b6534c9ae
commit 179236a122

View file

@ -380,8 +380,10 @@ static int init_names(struct gfs2_sbd *sdp, int silent)
if (!table[0])
table = sdp->sd_vfs->s_id;
strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
BUILD_BUG_ON(GFS2_LOCKNAME_LEN > GFS2_FSNAME_LEN);
strscpy(sdp->sd_proto_name, proto, GFS2_LOCKNAME_LEN);
strscpy(sdp->sd_table_name, table, GFS2_LOCKNAME_LEN);
table = sdp->sd_table_name;
while ((table = strchr(table, '/')))
@ -1352,13 +1354,13 @@ static int gfs2_parse_param(struct fs_context *fc, struct fs_parameter *param)
switch (o) {
case Opt_lockproto:
strlcpy(args->ar_lockproto, param->string, GFS2_LOCKNAME_LEN);
strscpy(args->ar_lockproto, param->string, GFS2_LOCKNAME_LEN);
break;
case Opt_locktable:
strlcpy(args->ar_locktable, param->string, GFS2_LOCKNAME_LEN);
strscpy(args->ar_locktable, param->string, GFS2_LOCKNAME_LEN);
break;
case Opt_hostdata:
strlcpy(args->ar_hostdata, param->string, GFS2_LOCKNAME_LEN);
strscpy(args->ar_hostdata, param->string, GFS2_LOCKNAME_LEN);
break;
case Opt_spectator:
args->ar_spectator = 1;