From fa205bd7f3b408972d5cc5bbc4bc8f855ef0dc42 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Fri, 26 Aug 2022 15:12:17 +0200 Subject: [PATCH] gfs2: Switch from strlcpy to strscpy 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 Signed-off-by: Andreas Gruenbacher --- fs/gfs2/ops_fstype.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 549879929c847..236b59ef93b68 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -381,8 +381,10 @@ 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, '/'))) @@ -1439,13 +1441,13 @@ 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; -- 2.39.5