Commits
Selvin Xavier committed a6c66d6a08b
RDMA/bnxt_re: Avoid accessing the device structure after it is freed When bnxt_re_ib_reg returns failure, the device structure gets freed. Driver tries to access the device pointer after it is freed. [ 4871.034744] Failed to register with netedev: 0xffffffa1 [ 4871.034765] infiniband (null): Failed to register with IB: 0xffffffea [ 4871.046430] ================================================================== [ 4871.046437] BUG: KASAN: use-after-free in bnxt_re_task+0x63/0x180 [bnxt_re] [ 4871.046439] Write of size 4 at addr ffff880fa8406f48 by task kworker/u48:2/17813 [ 4871.046443] CPU: 20 PID: 17813 Comm: kworker/u48:2 Kdump: loaded Tainted: G B OE 4.20.0-rc1+ #42 [ 4871.046444] Hardware name: Dell Inc. PowerEdge R730/0599V5, BIOS 1.0.4 08/28/2014 [ 4871.046447] Workqueue: bnxt_re bnxt_re_task [bnxt_re] [ 4871.046449] Call Trace: [ 4871.046454] dump_stack+0x91/0xeb [ 4871.046458] print_address_description+0x6a/0x2a0 [ 4871.046461] kasan_report+0x176/0x2d0 [ 4871.046463] ? bnxt_re_task+0x63/0x180 [bnxt_re] [ 4871.046466] bnxt_re_task+0x63/0x180 [bnxt_re] [ 4871.046470] process_one_work+0x216/0x5b0 [ 4871.046471] ? process_one_work+0x189/0x5b0 [ 4871.046475] worker_thread+0x4e/0x3d0 [ 4871.046479] kthread+0x10e/0x140 [ 4871.046480] ? process_one_work+0x5b0/0x5b0 [ 4871.046482] ? kthread_stop+0x220/0x220 [ 4871.046486] ret_from_fork+0x3a/0x50 [ 4871.046492] The buggy address belongs to the page: [ 4871.046494] page:ffffea003ea10180 count:0 mapcount:0 mapping:0000000000000000 index:0x0 [ 4871.046495] flags: 0x57ffffc0000000() [ 4871.046498] raw: 0057ffffc0000000 0000000000000000 ffffea003ea10188 0000000000000000 [ 4871.046500] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 4871.046501] page dumped because: kasan: bad access detected Avoid accessing the device structure once it is freed. Fixes: 497158aa5f52 ("RDMA/bnxt_re: Fix the ib_reg failure cleanup") Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>