f32b20e89e
In mlx4_en_update_priv(), dst->tx_ring[t] and dst->tx_cq[t]
are over-written by src->tx_ring[t] and src->tx_cq[t] without
first calling kfree.
One of the reproducible code paths is by doing 'ethtool -L'.
The fix is to do the kfree in mlx4_en_free_resources().
Here is the kmemleak report:
unreferenced object 0xffff880841211800 (size 2048):
comm "ethtool", pid 3096, jiffies 4294716940 (age 528.353s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff81930718>] kmemleak_alloc+0x28/0x50
[<ffffffff8120b213>] kmem_cache_alloc_trace+0x103/0x260
[<ffffffff8170e0a8>] mlx4_en_try_alloc_resources+0x118/0x1a0
[<ffffffff817065a9>] mlx4_en_set_ringparam+0x169/0x210
[<ffffffff818040c5>] dev_ethtool+0xae5/0x2190
[<ffffffff8181b898>] dev_ioctl+0x168/0x6f0
[<ffffffff817d7a72>] sock_do_ioctl+0x42/0x50
[<ffffffff817d819b>] sock_ioctl+0x21b/0x2d0
[<ffffffff81247a73>] do_vfs_ioctl+0x93/0x6a0
[<ffffffff812480f9>] SyS_ioctl+0x79/0x90
[<ffffffff8193d7ea>] entry_SYSCALL_64_fastpath+0x18/0xad
[<ffffffffffffffff>] 0xffffffffffffffff
unreferenced object 0xffff880841213000 (size 2048):
comm "ethtool", pid 3096, jiffies 4294716940 (age 528.353s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff81930718>] kmemleak_alloc+0x28/0x50
[<ffffffff8120b213>] kmem_cache_alloc_trace+0x103/0x260
[<ffffffff8170e0cb>] mlx4_en_try_alloc_resources+0x13b/0x1a0
[<ffffffff817065a9>] mlx4_en_set_ringparam+0x169/0x210
[<ffffffff818040c5>] dev_ethtool+0xae5/0x2190
[<ffffffff8181b898>] dev_ioctl+0x168/0x6f0
[<ffffffff817d7a72>] sock_do_ioctl+0x42/0x50
[<ffffffff817d819b>] sock_ioctl+0x21b/0x2d0
[<ffffffff81247a73>] do_vfs_ioctl+0x93/0x6a0
[<ffffffff812480f9>] SyS_ioctl+0x79/0x90
[<ffffffff8193d7ea>] entry_SYSCALL_64_fastpath+0x18/0xad
[<ffffffffffffffff>] 0xffffffffffffffff
(gdb) list *mlx4_en_try_alloc_resources+0x118
0xffffffff8170e0a8 is in mlx4_en_try_alloc_resources (drivers/net/ethernet/mellanox/mlx4/en_netdev.c:2145).
2140 if (!dst->tx_ring_num[t])
2141 continue;
2142
2143 dst->tx_ring[t] = kzalloc(sizeof(struct mlx4_en_tx_ring *) *
2144 MAX_TX_RINGS, GFP_KERNEL);
2145 if (!dst->tx_ring[t])
2146 goto err_free_tx;
2147
2148 dst->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
2149 MAX_TX_RINGS, GFP_KERNEL);
(gdb) list *mlx4_en_try_alloc_resources+0x13b
0xffffffff8170e0cb is in mlx4_en_try_alloc_resources (drivers/net/ethernet/mellanox/mlx4/en_netdev.c:2150).
2145 if (!dst->tx_ring[t])
2146 goto err_free_tx;
2147
2148 dst->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
2149 MAX_TX_RINGS, GFP_KERNEL);
2150 if (!dst->tx_cq[t]) {
2151 kfree(dst->tx_ring[t]);
2152 goto err_free_tx;
2153 }
2154 }
Fixes: ec25bc04ed8e ("net/mlx4_en: Add resilience in low memory systems")
Cc: Eugenia Emantayev <eugenia@mellanox.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.