5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Osama Muhammad <osmtendev@xxxxxxxxx> [ Upstream commit 8877243beafa7c6bfc42022cbfdf9e39b25bd4fa ] Syzkaller has reported a NULL pointer dereference when accessing rgd->rd_rgl in gfs2_rgrp_dump(). This can happen when creating rgd->rd_gl fails in read_rindex_entry(). Add a NULL pointer check in gfs2_rgrp_dump() to prevent that. Reported-and-tested-by: syzbot+da0fc229cc1ff4bb2e6d@xxxxxxxxxxxxxxxxxxxxxxxxx Link: https://syzkaller.appspot.com/bug?extid=da0fc229cc1ff4bb2e6d Fixes: 72244b6bc752 ("gfs2: improve debug information when lvb mismatches are found") Signed-off-by: Osama Muhammad <osmtendev@xxxxxxxxx> Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/gfs2/rgrp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index 6901cd85f1df..e4e85010ab5b 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -2316,7 +2316,7 @@ void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_rgrpd *rgd, (unsigned long long)rgd->rd_addr, rgd->rd_flags, rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes, rgd->rd_requested, rgd->rd_reserved, rgd->rd_extfail_pt); - if (rgd->rd_sbd->sd_args.ar_rgrplvb) { + if (rgd->rd_sbd->sd_args.ar_rgrplvb && rgd->rd_rgl) { struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl; gfs2_print_dbg(seq, "%s L: f:%02x b:%u i:%u\n", fs_id_buf, -- 2.43.0
