diff options
| author | Lv Yunlong <lyl2019@mail.ustc.edu.cn> | 2021-04-25 18:16:47 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-05-14 09:44:32 +0200 |
| commit | 30b9e92d0b5e5d5dc1101ab856c17009537cbca4 (patch) | |
| tree | 9e2de065e65bfa823909325e774ce394ef0398f4 /drivers/infiniband/sw | |
| parent | 55fcdd1258faaecca74b91b88cc0921f9edd775d (diff) | |
RDMA/siw: Fix a use after free in siw_alloc_mr
[ Upstream commit 3093ee182f01689b89e9f8797b321603e5de4f63 ]
Our code analyzer reported a UAF.
In siw_alloc_mr(), it calls siw_mr_add_mem(mr,..). In the implementation of
siw_mr_add_mem(), mem is assigned to mr->mem and then mem is freed via
kfree(mem) if xa_alloc_cyclic() failed. Here, mr->mem still point to a
freed object. After, the execution continue up to the err_out branch of
siw_alloc_mr, and the freed mr->mem is used in siw_mr_drop_mem(mr).
My patch moves "mr->mem = mem" behind the if (xa_alloc_cyclic(..)<0) {}
section, to avoid the uaf.
Fixes: 2251334dcac9 ("rdma/siw: application buffer management")
Link: https://lore.kernel.org/r/20210426011647.3561-1-lyl2019@mail.ustc.edu.cn
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Reviewed-by: Bernard Metzler <bmt@zurich.ihm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/infiniband/sw')
| -rw-r--r-- | drivers/infiniband/sw/siw/siw_mem.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c index e99983f07663..8bffa6e013fc 100644 --- a/drivers/infiniband/sw/siw/siw_mem.c +++ b/drivers/infiniband/sw/siw/siw_mem.c @@ -106,8 +106,6 @@ int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj, mem->perms = rights & IWARP_ACCESS_MASK; kref_init(&mem->ref); - mr->mem = mem; - get_random_bytes(&next, 4); next &= 0x00ffffff; @@ -116,6 +114,8 @@ int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj, kfree(mem); return -ENOMEM; } + + mr->mem = mem; /* Set the STag index part */ mem->stag = id << 8; mr->base_mr.lkey = mr->base_mr.rkey = mem->stag; |