Eugeniu Rosca 79514ef670 ravb: Fix use-after-free on `ifconfig eth0 down` ... Commit a47b70ea86 ("ravb: unmap descriptors when freeing rings") has introduced the issue seen in [1] reproduced on H3ULCB board. Fix this by relocating the RX skb ringbuffer free operation, so that swiotlb page unmapping can be done first. Freeing of aligned TX buffers is not relevant to the issue seen in [1]. Still, reposition TX free calls as well, to have all kfree() operations performed consistently _after_ dma_unmap_*()/dma_free_*(). [1] Console screenshot with the problem reproduced: salvator-x login: root root@salvator-x:~# ifconfig eth0 up Micrel KSZ9031 Gigabit PHY e6800000.ethernet-ffffffff:00: \ attached PHY driver [Micrel KSZ9031 Gigabit PHY] \ (mii_bus:phy_addr=e6800000.ethernet-ffffffff:00, irq=235) IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready root@salvator-x:~# root@salvator-x:~# ifconfig eth0 down ================================================================== BUG: KASAN: use-after-free in swiotlb_tbl_unmap_single+0xc4/0x35c Write of size 1538 at addr ffff8006d884f780 by task ifconfig/1649 CPU: 0 PID: 1649 Comm: ifconfig Not tainted 4.12.0-rc4-00004-g112eb07287d1 #32 Hardware name: Renesas H3ULCB board based on r8a7795 (DT) Call trace: [<ffff20000808f11c>] dump_backtrace+0x0/0x3a4 [<ffff20000808f4d4>] show_stack+0x14/0x1c [<ffff20000865970c>] dump_stack+0xf8/0x150 [<ffff20000831f8b0>] print_address_description+0x7c/0x330 [<ffff200008320010>] kasan_report+0x2e0/0x2f4 [<ffff20000831eac0>] check_memory_region+0x20/0x14c [<ffff20000831f054>] memcpy+0x48/0x68 [<ffff20000869ed50>] swiotlb_tbl_unmap_single+0xc4/0x35c [<ffff20000869fcf4>] unmap_single+0x90/0xa4 [<ffff20000869fd14>] swiotlb_unmap_page+0xc/0x14 [<ffff2000080a2974>] __swiotlb_unmap_page+0xcc/0xe4 [<ffff2000088acdb8>] ravb_ring_free+0x514/0x870 [<ffff2000088b25dc>] ravb_close+0x288/0x36c [<ffff200008aaf8c4>] __dev_close_many+0x14c/0x174 [<ffff200008aaf9b4>] __dev_close+0xc8/0x144 [<ffff200008ac2100>] __dev_change_flags+0xd8/0x194 [<ffff200008ac221c>] dev_change_flags+0x60/0xb0 [<ffff200008ba2dec>] devinet_ioctl+0x484/0x9d4 [<ffff200008ba7b78>] inet_ioctl+0x190/0x194 [<ffff200008a78c44>] sock_do_ioctl+0x78/0xa8 [<ffff200008a7a128>] sock_ioctl+0x110/0x3c4 [<ffff200008365a70>] vfs_ioctl+0x90/0xa0 [<ffff200008365dbc>] do_vfs_ioctl+0x148/0xc38 [<ffff2000083668f0>] SyS_ioctl+0x44/0x74 [<ffff200008083770>] el0_svc_naked+0x24/0x28 The buggy address belongs to the page: page:ffff7e001b6213c0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000000() raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff raw: 0000000000000000 ffff7e001b6213e0 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8006d884f680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8006d884f700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8006d884f780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8006d884f800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8006d884f880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== Disabling lock debugging due to kernel taint root@salvator-x:~# Fixes: a47b70ea86 ("ravb: unmap descriptors when freeing rings") Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com> Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2017-06-06 16:02:22 -04:00
..
Kconfig	ptp_clock: Allow for it to be optional	2016-11-16 09:26:34 +01:00
Makefile	Renesas Ethernet AVB PTP clock driver	2015-06-11 00:24:12 -07:00
ravb.h	ravb: Add tx and rx clock internal delays mode of APSR	2017-01-29 18:35:43 -05:00
ravb_main.c	ravb: Fix use-after-free on `ifconfig eth0 down`	2017-06-06 16:02:22 -04:00
ravb_ptp.c	ravb: make ravb_ptp_interrupt() *void*	2016-04-14 00:48:33 -04:00
sh_eth.c	sh_eth: Do not print an error message for probe deferral	2017-05-18 11:21:07 -04:00
sh_eth.h	sh_eth: add missing EESIPR bits	2017-01-30 22:05:43 -05:00