From ca959e328b2243687aa0b95de01414d13e4f3ade Mon Sep 17 00:00:00 2001 From: Gaosheng Cui Date: Sat, 26 Oct 2024 18:26:58 +0800 Subject: [PATCH] bcachefs: fix possible null-ptr-deref in __bch2_ec_stripe_head_get() The function ec_new_stripe_head_alloc() returns nullptr if kzalloc() fails. It is crucial to verify its return value before dereferencing it to avoid a potential nullptr dereference. Fixes: 035d72f72c91 ("bcachefs: bch2_ec_stripe_head_get() now checks for change in rw devices") Signed-off-by: Gaosheng Cui Signed-off-by: Kent Overstreet --- fs/bcachefs/ec.c | 4 ++++ fs/bcachefs/errcode.h | 1 + 2 files changed, 5 insertions(+) diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c index a0aa5bb467d9..749dcf368841 100644 --- a/fs/bcachefs/ec.c +++ b/fs/bcachefs/ec.c @@ -1870,6 +1870,10 @@ __bch2_ec_stripe_head_get(struct btree_trans *trans, } h = ec_new_stripe_head_alloc(c, disk_label, algo, redundancy, watermark); + if (!h) { + h = ERR_PTR(-BCH_ERR_ENOMEM_stripe_head_alloc); + goto err; + } found: if (h->rw_devs_change_count != c->rw_devs_change_count) ec_stripe_head_devs_update(c, h); diff --git a/fs/bcachefs/errcode.h b/fs/bcachefs/errcode.h index b6cbd716000b..a1bc6c7a8ba0 100644 --- a/fs/bcachefs/errcode.h +++ b/fs/bcachefs/errcode.h @@ -83,6 +83,7 @@ x(ENOMEM, ENOMEM_fs_other_alloc) \ x(ENOMEM, ENOMEM_dev_alloc) \ x(ENOMEM, ENOMEM_disk_accounting) \ + x(ENOMEM, ENOMEM_stripe_head_alloc) \ x(ENOSPC, ENOSPC_disk_reservation) \ x(ENOSPC, ENOSPC_bucket_alloc) \ x(ENOSPC, ENOSPC_disk_label_add) \