iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

gfs2: assign rgrp glock before compute_bitstructs

Browse Source 
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>
This commit is contained in:
Bob Peterson 2022-01-17 10:25:07 -05:00 committed by Andreas Gruenbacher
parent 754e0b0e35
commit 428f651cb8
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
fs/gfs2/rgrp.c
View File

@ -922,15 +922,15 @@ static int read_rindex_entry(struct gfs2_inode *ip)
spin_lock_init(&rgd->rd_rsspin);
mutex_init(&rgd->rd_mutex);
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_PREFERRED;
if (rgd->rd_data > sdp->sd_max_rg_data)
@ -944,6 +944,7 @@ 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: