[PATCH AUTOSEL 4.4 08/16] net: hns: Fix use after free identified by SLUB debug

[PATCH AUTOSEL 4.4 08/16] net: hns: Fix use after free identified by SLUB debug

[Sasha Levin]

From: Yonglong Liu <liuyonglong@huawei.com>

[ Upstream commit bb989501abcafa0de5f18b0ec0ec459b5b817908 ]

When enable SLUB debug, than remove hns_enet_drv module, SLUB debug will
identify a use after free bug:

[134.189505] Unable to handle kernel paging request at virtual address
		006b6b6b6b6b6b6b
[134.197553] Mem abort info:
[134.200381]   ESR = 0x96000004
[134.203487]   Exception class = DABT (current EL), IL = 32 bits
[134.209497]   SET = 0, FnV = 0
[134.212596]   EA = 0, S1PTW = 0
[134.215777] Data abort info:
[134.218701]   ISV = 0, ISS = 0x00000004
[134.222596]   CM = 0, WnR = 0
[134.225606] [006b6b6b6b6b6b6b] address between user and kernel address ranges
[134.232851] Internal error: Oops: 96000004 [#1] SMP
[134.237798] CPU: 21 PID: 27834 Comm: rmmod Kdump: loaded Tainted: G
		OE     4.19.5-1.2.34.aarch64 #1
[134.247856] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.58 10/24/2018
[134.255181] pstate: 20000005 (nzCv daif -PAN -UAO)
[134.260044] pc : hns_ae_put_handle+0x38/0x60
[134.264372] lr : hns_ae_put_handle+0x24/0x60
[134.268700] sp : ffff00001be93c50
[134.272054] x29: ffff00001be93c50 x28: ffff802faaec8040
[134.277442] x27: 0000000000000000 x26: 0000000000000000
[134.282830] x25: 0000000056000000 x24: 0000000000000015
[134.288284] x23: ffff0000096fe098 x22: ffff000001050070
[134.293671] x21: ffff801fb3c044a0 x20: ffff80afb75ec098
[134.303287] x19: ffff80afb75ec098 x18: 0000000000000000
[134.312945] x17: 0000000000000000 x16: 0000000000000000
[134.322517] x15: 0000000000000002 x14: 0000000000000000
[134.332030] x13: dead000000000100 x12: ffff7e02bea3c988
[134.341487] x11: ffff80affbee9e68 x10: 0000000000000000
[134.351033] x9 : 6fffff8000008101 x8 : 0000000000000000
[134.360569] x7 : dead000000000100 x6 : ffff000009579748
[134.370059] x5 : 0000000000210d00 x4 : 0000000000000000
[134.379550] x3 : 0000000000000001 x2 : 0000000000000000
[134.388813] x1 : 6b6b6b6b6b6b6b6b x0 : 0000000000000000
[134.397993] Process rmmod (pid: 27834, stack limit = 0x00000000d474b7fd)
[134.408498] Call trace:
[134.414611]  hns_ae_put_handle+0x38/0x60
[134.422208]  hnae_put_handle+0xd4/0x108
[134.429563]  hns_nic_dev_remove+0x60/0xc0 [hns_enet_drv]
[134.438342]  platform_drv_remove+0x2c/0x70
[134.445958]  device_release_driver_internal+0x174/0x208
[134.454810]  driver_detach+0x70/0xd8
[134.461913]  bus_remove_driver+0x64/0xe8
[134.469396]  driver_unregister+0x34/0x60
[134.476822]  platform_driver_unregister+0x20/0x30
[134.485130]  hns_nic_dev_driver_exit+0x14/0x6e4 [hns_enet_drv]
[134.494634]  __arm64_sys_delete_module+0x238/0x290

struct hnae_handle is a member of struct hnae_vf_cb, so when vf_cb is
freed, than use hnae_handle will cause use after free panic.

This patch frees vf_cb after hnae_handle used.

Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/hisilicon/hns/hns_ae_adapt.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns/hns_ae_adapt.c b/drivers/net/ethernet/hisilicon/hns/hns_ae_adapt.c
index 1a16c0307b47..bd36fbe81ad2 100644
--- a/drivers/net/ethernet/hisilicon/hns/hns_ae_adapt.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_ae_adapt.c
@@ -188,12 +188,10 @@ static void hns_ae_put_handle(struct hnae_handle *handle)
 	struct hnae_vf_cb *vf_cb = hns_ae_get_vf_cb(handle);
 	int i;
 
-	vf_cb->mac_cb	 = NULL;
-
-	kfree(vf_cb);
-
 	for (i = 0; i < handle->q_num; i++)
 		hns_ae_get_ring_pair(handle->qs[i])->used_by_vf = 0;
+
+	kfree(vf_cb);
 }
 
 static void hns_ae_ring_enable_all(struct hnae_handle *handle, int val)
-- 
2.19.1

[PATCH AUTOSEL 4.4 13/16] isdn: i4l: isdn_tty: Fix some concurrency double-free bugs

[Sasha Levin]

From: Jia-Ju Bai <baijiaju1990@gmail.com>

[ Upstream commit 2ff33d6637393fe9348357285931811b76e1402f ]

The functions isdn_tty_tiocmset() and isdn_tty_set_termios() may be
concurrently executed.

isdn_tty_tiocmset
  isdn_tty_modem_hup
    line 719: kfree(info->dtmf_state);
    line 721: kfree(info->silence_state);
    line 723: kfree(info->adpcms);
    line 725: kfree(info->adpcmr);

isdn_tty_set_termios
  isdn_tty_modem_hup
    line 719: kfree(info->dtmf_state);
    line 721: kfree(info->silence_state);
    line 723: kfree(info->adpcms);
    line 725: kfree(info->adpcmr);

Thus, some concurrency double-free bugs may occur.

These possible bugs are found by a static tool written by myself and
my manual code review.

To fix these possible bugs, the mutex lock "modem_info_mutex" used in
isdn_tty_tiocmset() is added in isdn_tty_set_termios().

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/isdn/i4l/isdn_tty.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c
index 2175225af742..8291e9cc949a 100644
--- a/drivers/isdn/i4l/isdn_tty.c
+++ b/drivers/isdn/i4l/isdn_tty.c
@@ -1459,15 +1459,19 @@ isdn_tty_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
 {
 	modem_info *info = (modem_info *) tty->driver_data;
 
+	mutex_lock(&modem_info_mutex);
 	if (!old_termios)
 		isdn_tty_change_speed(info);
 	else {
 		if (tty->termios.c_cflag == old_termios->c_cflag &&
 		    tty->termios.c_ispeed == old_termios->c_ispeed &&
-		    tty->termios.c_ospeed == old_termios->c_ospeed)
+		    tty->termios.c_ospeed == old_termios->c_ospeed) {
+			mutex_unlock(&modem_info_mutex);
 			return;
+		}
 		isdn_tty_change_speed(info);
 	}
+	mutex_unlock(&modem_info_mutex);
 }
 
 /*
-- 
2.19.1

[PATCH AUTOSEL 4.4 14/16] atm: he: fix sign-extension overflow on large shift

[Sasha Levin]

From: Colin Ian King <colin.king@canonical.com>

[ Upstream commit cb12d72b27a6f41325ae23a11033cf5fedfa1b97 ]

Shifting the 1 by exp by an int can lead to sign-extension overlow when
exp is 31 since 1 is an signed int and sign-extending this result to an
unsigned long long will set the upper 32 bits.  Fix this by shifting an
unsigned long.

Detected by cppcheck:
(warning) Shifting signed 32-bit value by 31 bits is undefined behaviour

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/atm/he.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/atm/he.c b/drivers/atm/he.c
index 0f5cb37636bc..010581e8bee0 100644
--- a/drivers/atm/he.c
+++ b/drivers/atm/he.c
@@ -717,7 +717,7 @@ static int he_init_cs_block_rcm(struct he_dev *he_dev)
 			instead of '/ 512', use '>> 9' to prevent a call
 			to divdu3 on x86 platforms
 		*/
-		rate_cps = (unsigned long long) (1 << exp) * (man + 512) >> 9;
+		rate_cps = (unsigned long long) (1UL << exp) * (man + 512) >> 9;
 
 		if (rate_cps < 10)
 			rate_cps = 10;	/* 2.2.1 minimum payload rate is 10 cps */
-- 
2.19.1

[PATCH AUTOSEL 4.4 16/16] isdn: avm: Fix string plus integer warning from Clang

[Sasha Levin]

From: Nathan Chancellor <natechancellor@gmail.com>

[ Upstream commit 7afa81c55fca0cad589722cb4bce698b4803b0e1 ]

A recent commit in Clang expanded the -Wstring-plus-int warning, showing
some odd behavior in this file.

drivers/isdn/hardware/avm/b1.c:426:30: warning: adding 'int' to a string does not append to the string [-Wstring-plus-int]
                cinfo->version[j] = "\0\0" + 1;
                                    ~~~~~~~^~~
drivers/isdn/hardware/avm/b1.c:426:30: note: use array indexing to silence this warning
                cinfo->version[j] = "\0\0" + 1;
                                           ^
                                    &      [  ]
1 warning generated.

This is equivalent to just "\0". Nick pointed out that it is smarter to
use "" instead of "\0" because "" is used elsewhere in the kernel and
can be deduplicated at the linking stage.

Link: https://github.com/ClangBuiltLinux/linux/issues/309
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/isdn/hardware/avm/b1.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/isdn/hardware/avm/b1.c b/drivers/isdn/hardware/avm/b1.c
index 4d9b195547c5..df2a10157720 100644
--- a/drivers/isdn/hardware/avm/b1.c
+++ b/drivers/isdn/hardware/avm/b1.c
@@ -423,7 +423,7 @@ void b1_parse_version(avmctrl_info *cinfo)
 	int i, j;
 
 	for (j = 0; j < AVM_MAXVERSION; j++)
-		cinfo->version[j] = "\0\0" + 1;
+		cinfo->version[j] = "";
 	for (i = 0, j = 0;
 	     j < AVM_MAXVERSION && i < cinfo->versionlen;
 	     j++, i += cinfo->versionbuf[i] + 1)
-- 
2.19.1