[PATCH 6.0 0601/1073] RDMA/rxe: Fix mr->map double free

Greg Kroah-Hartman
2022-12-28T16:13:24Z

From: Li Zhijian <lizhijian@fujitsu.com>

[ Upstream commit 7d984dac8f6bf4ebd3398af82b357e1d181ecaac ]

rxe_mr_cleanup() which tries to free mr->map again will be called when
rxe_mr_init_user() fails:

CPU: 0 PID: 4917 Comm: rdma_flush_serv Kdump: loaded Not tainted 6.1.0-rc1-roce-flush+ #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x45/0x5d
panic+0x19e/0x349
end_report.part.0+0x54/0x7c
kasan_report.cold+0xa/0xf
rxe_mr_cleanup+0x9d/0xf0 [rdma_rxe]
__rxe_cleanup+0x10a/0x1e0 [rdma_rxe]
rxe_reg_user_mr+0xb7/0xd0 [rdma_rxe]
ib_uverbs_reg_mr+0x26a/0x480 [ib_uverbs]
ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0x1a2/0x250 [ib_uverbs]
ib_uverbs_cmd_verbs+0x1397/0x15a0 [ib_uverbs]

This issue was firstly exposed since commit b18c7da63fcb ("RDMA/rxe: Fix
memory leak in error path code") and then we fixed it in commit
8ff5f5d9d8cf ("RDMA/rxe: Prevent double freeing rxe_map_set()") but this
fix was reverted together at last by commit 1e75550648da (Revert
"RDMA/rxe: Create duplicate mapping tables for FMRs")

Simply let rxe_mr_cleanup() always handle freeing the mr->map once it is
successfully allocated.

Fixes: 1e75550648da ("Revert "RDMA/rxe: Create duplicate mapping tables for FMRs"")
Link: https://lore.kernel.org/r/1667099073-2-1-git-send-email-lizhijian@fujitsu.com
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/sw/rxe/rxe_mr.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
index af34f198e645..8cd6f1b165d5 100644
--- a/drivers/infiniband/sw/rxe/rxe_mr.c
+++ b/drivers/infiniband/sw/rxe/rxe_mr.c
@@ -99,6 +99,7 @@ static int rxe_mr_alloc(struct rxe_mr *mr, int num_buf)
kfree(mr->map[i]);

kfree(mr->map);
+ mr->map = NULL;
err1:
return -ENOMEM;
}
@@ -122,7 +123,6 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
int num_buf;
void *vaddr;
int err;
- int i;

umem = ib_umem_get(&rxe->ib_dev, start, length, access);
if (IS_ERR(umem)) {
@@ -163,9 +163,8 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,
pr_warn("%s: Unable to get virtual address\n",
__func__);
err = -ENOMEM;
- goto err_cleanup_map;
+ goto err_release_umem;
}
-
buf->addr = (uintptr_t)vaddr;
buf->size = PAGE_SIZE;
num_buf++;
@@ -185,10 +184,6 @@ int rxe_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, u64 iova,

return 0;

-err_cleanup_map:
- for (i = 0; i < mr->num_map; i++)
- kfree(mr->map[i]);
- kfree(mr->map);
err_release_umem:
ib_umem_release(umem);
err_out:
--
2.35.1