[ 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@syzkaller.appspotmail.com
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@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f38e998fbbb5da6a097ecd4b2700ba95eabab0c9 ]
Pass a non-NULL minext to gfs2_rbm_find even for single-block allocations. In
gfs2_rbm_find, also set rgd->rd_extfail_pt when a single-block allocation
fails in a resource group: there is no reason for treating that case
differently. In gfs2_reservation_check_and_update, only check how many free
blocks we have if more than one block is requested; we already know there's at
least one free block.
In addition, when allocating N blocks fails in gfs2_rbm_find, we need to set
rd_extfail_pt to N - 1 rather than N: rd_extfail_pt defines the biggest
allocation that might still succeed.
Finally, reset rd_extfail_pt when updating the resource group statistics in
update_rgrp_lvb, as we already do in gfs2_rgrp_bh_get.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Stable-dep-of: 8877243beafa ("gfs2: Fix kernel NULL pointer dereference in gfs2_rgrp_dump")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2fdc2fa21bc72ec06c0c9f0e30b88fe1f2486b75 ]
This reverts commit e79e0e1428188b24c3b57309ffa54a33c4ae40c4.
It turns out that we're only setting the GBF_FULL flag of a bitmap if we've
been scanning from the beginning of the bitmap until the end and we haven't
found a single free block, and we're not skipping reservations in that process,
either. This means that in gfs2_rbm_find, we can always skip bitmaps with the
GBF_FULL flag set.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Stable-dep-of: 8877243beafa ("gfs2: Fix kernel NULL pointer dereference in gfs2_rgrp_dump")
Signed-off-by: Sasha Levin <sashal@kernel.org>
