From: Bob Peterson <rpeterso@redhat.com> stable inclusion from stable-v5.10.113 commit 04dd45d9776eb4802df8b0a0a6fcdf27842fbdd1 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 428f651cb80b227af47fc302e4931791f2fb4741 upstream. Before this patch, function read_rindex_entry called compute_bitstructs before it allocated a glock for the rgrp. But if compute_bitstructs found a problem with the rgrp, it called gfs2_consist_rgrpd, and that called gfs2_dump_glock for rgd->rd_gl which had not yet been assigned. read_rindex_entry compute_bitstructs gfs2_consist_rgrpd gfs2_dump_glock <---------rgd->rd_gl was not set. This patch changes read_rindex_entry so it assigns an rgrp glock before calling compute_bitstructs so gfs2_dump_glock does not reference an unassigned pointer. If an error is discovered, the glock must also be put, so a new goto and label were added. Reported-by: syzbot+c6fd14145e2f62ca0784@syzkaller.appspotmail.com Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Acked-by: Xie XiuQi <xiexiuqi@huawei.com> --- fs/gfs2/rgrp.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index dc55b029afaa..c5bde789a16d 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -906,15 +906,15 @@ static int read_rindex_entry(struct gfs2_inode *ip) rgd->rd_bitbytes = be32_to_cpu(buf.ri_bitbytes); spin_lock_init(&rgd->rd_rsspin); - error = compute_bitstructs(rgd); - if (error) - goto fail; - error = gfs2_glock_get(sdp, rgd->rd_addr, &gfs2_rgrp_glops, CREATE, &rgd->rd_gl); if (error) goto fail; + error = compute_bitstructs(rgd); + if (error) + goto fail_glock; + rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lksb.sb_lvbptr; rgd->rd_flags &= ~(GFS2_RDF_UPTODATE | GFS2_RDF_PREFERRED); if (rgd->rd_data > sdp->sd_max_rg_data) @@ -928,6 +928,7 @@ static int read_rindex_entry(struct gfs2_inode *ip) } error = 0; /* someone else read in the rgrp; free it and ignore it */ +fail_glock: gfs2_glock_put(rgd->rd_gl); fail: -- 2.20.1