From: Sven Schnelle Date: Fri, 28 Mar 2008 21:15:55 +0000 (-0700) Subject: afs: prevent double cell registration X-Git-Tag: v3.12-rc1~22234 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5214b729e1c2dc3af8f55e6c4c548844c3bea0f5;p=kernel%2Fkernel-generic.git afs: prevent double cell registration kafs doesn't check if the cell already exists - so if you do an echo "add newcell.org 1.2.3.4" >/proc/fs/afs/cells it will try to create this cell again. kobject will also complain about a double registration. To prevent such problems, return -EEXIST in that case. Signed-off-by: Sven Schnelle Signed-off-by: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/afs/cell.c b/fs/afs/cell.c index 970d38f..788865d 100644 --- a/fs/afs/cell.c +++ b/fs/afs/cell.c @@ -127,14 +127,20 @@ struct afs_cell *afs_cell_create(const char *name, char *vllist) _enter("%s,%s", name, vllist); + down_write(&afs_cells_sem); + read_lock(&afs_cells_lock); + list_for_each_entry(cell, &afs_cells, link) { + if (strcasecmp(cell->name, name) == 0) + goto duplicate_name; + } + read_unlock(&afs_cells_lock); + cell = afs_cell_alloc(name, vllist); if (IS_ERR(cell)) { _leave(" = %ld", PTR_ERR(cell)); return cell; } - down_write(&afs_cells_sem); - /* add a proc directory for this cell */ ret = afs_proc_cell_setup(cell); if (ret < 0) @@ -167,6 +173,11 @@ error: kfree(cell); _leave(" = %d", ret); return ERR_PTR(ret); + +duplicate_name: + read_unlock(&afs_cells_lock); + up_write(&afs_cells_sem); + return ERR_PTR(-EEXIST); } /*