From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Hi Greg-KH,
Here are two target patches for v4.9.y stable, which did not apply
due to minor context changes.
The series has been cut against v4.9.76. Please apply at your earliest
convenience.
Thank you,
--nab
Nicholas Bellinger (2):
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
drivers/target/iscsi/iscsi_target.c | 20 +++++++-------------
drivers/target/target_core_tmr.c | 9 +++++++++
drivers/target/target_core_transport.c | 2 ++
include/target/target_core_base.h | 1 +
4 files changed, 19 insertions(+), 13 deletions(-)
--
1.8.5.3
This is a note to let you know that I've just added the patch titled
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 1c21a48055a67ceb693e9c2587824a8de60a217c Mon Sep 17 00:00:00 2001
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Date: Fri, 27 Oct 2017 22:19:26 -0800
Subject: target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
commit 1c21a48055a67ceb693e9c2587824a8de60a217c upstream.
This patch fixes bug where early se_cmd exceptions that occur
before backend execution can result in use-after-free if/when
a subsequent ABORT_TASK occurs for the same tag.
Since an early se_cmd exception will have had se_cmd added to
se_session->sess_cmd_list via target_get_sess_cmd(), it will
not have CMD_T_COMPLETE set by the usual target_complete_cmd()
backend completion path.
This causes a subsequent ABORT_TASK + __target_check_io_state()
to signal ABORT_TASK should proceed. As core_tmr_abort_task()
executes, it will bring the outstanding se_cmd->cmd_kref count
down to zero releasing se_cmd, after se_cmd has already been
queued with error status into fabric driver response path code.
To address this bug, introduce a CMD_T_PRE_EXECUTE bit that is
set at target_get_sess_cmd() time, and cleared immediately before
backend driver dispatch in target_execute_cmd() once CMD_T_ACTIVE
is set.
Then, check CMD_T_PRE_EXECUTE within __target_check_io_state() to
determine when an early exception has occured, and avoid aborting
this se_cmd since it will have already been queued into fabric
driver response path code.
Reported-by: Donald White <dew(a)datera.io>
Cc: Donald White <dew(a)datera.io>
Cc: Mike Christie <mchristi(a)redhat.com>
Cc: Hannes Reinecke <hare(a)suse.com>
Signed-off-by: Nicholas Bellinger <nab(a)linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/target/target_core_tmr.c | 9 +++++++++
drivers/target/target_core_transport.c | 2 ++
include/target/target_core_base.h | 1 +
3 files changed, 12 insertions(+)
--- a/drivers/target/target_core_tmr.c
+++ b/drivers/target/target_core_tmr.c
@@ -133,6 +133,15 @@ static bool __target_check_io_state(stru
spin_unlock(&se_cmd->t_state_lock);
return false;
}
+ if (se_cmd->transport_state & CMD_T_PRE_EXECUTE) {
+ if (se_cmd->scsi_status) {
+ pr_debug("Attempted to abort io tag: %llu early failure"
+ " status: 0x%02x\n", se_cmd->tag,
+ se_cmd->scsi_status);
+ spin_unlock(&se_cmd->t_state_lock);
+ return false;
+ }
+ }
if (sess->sess_tearing_down || se_cmd->cmd_wait_set) {
pr_debug("Attempted to abort io tag: %llu already shutdown,"
" skipping\n", se_cmd->tag);
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1933,6 +1933,7 @@ void target_execute_cmd(struct se_cmd *c
}
cmd->t_state = TRANSPORT_PROCESSING;
+ cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
spin_unlock_irq(&cmd->t_state_lock);
@@ -2572,6 +2573,7 @@ int target_get_sess_cmd(struct se_cmd *s
ret = -ESHUTDOWN;
goto out;
}
+ se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
out:
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -496,6 +496,7 @@ struct se_cmd {
#define CMD_T_BUSY (1 << 9)
#define CMD_T_TAS (1 << 10)
#define CMD_T_FABRIC_STOP (1 << 11)
+#define CMD_T_PRE_EXECUTE (1 << 12)
spinlock_t t_state_lock;
struct kref cmd_kref;
struct completion t_transport_stop_comp;
Patches currently in stable-queue which might be from nab(a)linux-iscsi.org are
queue-4.4/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
queue-4.4/target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch
This is a note to let you know that I've just added the patch titled
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From ae072726f6109bb1c94841d6fb3a82dde298ea85 Mon Sep 17 00:00:00 2001
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Date: Fri, 27 Oct 2017 12:32:59 -0700
Subject: iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
commit ae072726f6109bb1c94841d6fb3a82dde298ea85 upstream.
Since commit 59b6986dbf fixed a potential NULL pointer dereference
by allocating a se_tmr_req for ISCSI_TM_FUNC_TASK_REASSIGN, the
se_tmr_req is currently leaked by iscsit_free_cmd() because no
iscsi_cmd->se_cmd.se_tfo was associated.
To address this, treat ISCSI_TM_FUNC_TASK_REASSIGN like any other
TMR and call transport_init_se_cmd() + target_get_sess_cmd() to
setup iscsi_cmd->se_cmd.se_tfo with se_cmd->cmd_kref of 2.
This will ensure normal release operation once se_cmd->cmd_kref
reaches zero and target_release_cmd_kref() is invoked, se_tmr_req
will be released via existing target_free_cmd_mem() and
core_tmr_release_req() code.
Reported-by: Donald White <dew(a)datera.io>
Cc: Donald White <dew(a)datera.io>
Cc: Mike Christie <mchristi(a)redhat.com>
Cc: Hannes Reinecke <hare(a)suse.com>
Signed-off-by: Nicholas Bellinger <nab(a)linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/target/iscsi/iscsi_target.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -1759,7 +1759,6 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
struct iscsi_tmr_req *tmr_req;
struct iscsi_tm *hdr;
int out_of_order_cmdsn = 0, ret;
- bool sess_ref = false;
u8 function, tcm_function = TMR_UNKNOWN;
hdr = (struct iscsi_tm *) buf;
@@ -1801,18 +1800,17 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
buf);
}
+ transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
+ conn->sess->se_sess, 0, DMA_NONE,
+ TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
+
+ target_get_sess_cmd(&cmd->se_cmd, true);
+
/*
* TASK_REASSIGN for ERL=2 / connection stays inside of
* LIO-Target $FABRIC_MOD
*/
if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
- transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
- conn->sess->se_sess, 0, DMA_NONE,
- TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
-
- target_get_sess_cmd(&cmd->se_cmd, true);
- sess_ref = true;
-
switch (function) {
case ISCSI_TM_FUNC_ABORT_TASK:
tcm_function = TMR_ABORT_TASK;
@@ -1951,12 +1949,8 @@ attach:
* For connection recovery, this is also the default action for
* TMR TASK_REASSIGN.
*/
- if (sess_ref) {
- pr_debug("Handle TMR, using sess_ref=true check\n");
- target_put_sess_cmd(&cmd->se_cmd);
- }
-
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
+ target_put_sess_cmd(&cmd->se_cmd);
return 0;
}
EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
Patches currently in stable-queue which might be from nab(a)linux-iscsi.org are
queue-4.4/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
queue-4.4/target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Hi Greg-KH,
Here are two target patches for v4.4.y stable, which did not apply
due to minor context changes.
The series has been cut against v4.4.111. Please apply at your earliest
convenience.
Thank you,
--nab
Nicholas Bellinger (2):
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
drivers/target/iscsi/iscsi_target.c | 20 +++++++-------------
drivers/target/target_core_tmr.c | 9 +++++++++
drivers/target/target_core_transport.c | 2 ++
include/target/target_core_base.h | 1 +
4 files changed, 19 insertions(+), 13 deletions(-)
--
1.8.5.3
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Hi Greg-KH,
Here are two target patches for v3.18.y stable, which did not apply
due to minor context changes.
The series has been cut against v3.18.91. Please apply at your earliest
convenience.
Thank you,
--nab
Nicholas Bellinger (2):
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
drivers/target/iscsi/iscsi_target.c | 21 +++++++--------------
drivers/target/target_core_tmr.c | 9 +++++++++
drivers/target/target_core_transport.c | 2 ++
include/target/target_core_base.h | 1 +
4 files changed, 19 insertions(+), 14 deletions(-)
--
1.8.5.3
This is a note to let you know that I've just added the patch titled
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 1c21a48055a67ceb693e9c2587824a8de60a217c Mon Sep 17 00:00:00 2001
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Date: Fri, 27 Oct 2017 22:19:26 -0800
Subject: target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
commit 1c21a48055a67ceb693e9c2587824a8de60a217c upstream.
This patch fixes bug where early se_cmd exceptions that occur
before backend execution can result in use-after-free if/when
a subsequent ABORT_TASK occurs for the same tag.
Since an early se_cmd exception will have had se_cmd added to
se_session->sess_cmd_list via target_get_sess_cmd(), it will
not have CMD_T_COMPLETE set by the usual target_complete_cmd()
backend completion path.
This causes a subsequent ABORT_TASK + __target_check_io_state()
to signal ABORT_TASK should proceed. As core_tmr_abort_task()
executes, it will bring the outstanding se_cmd->cmd_kref count
down to zero releasing se_cmd, after se_cmd has already been
queued with error status into fabric driver response path code.
To address this bug, introduce a CMD_T_PRE_EXECUTE bit that is
set at target_get_sess_cmd() time, and cleared immediately before
backend driver dispatch in target_execute_cmd() once CMD_T_ACTIVE
is set.
Then, check CMD_T_PRE_EXECUTE within __target_check_io_state() to
determine when an early exception has occured, and avoid aborting
this se_cmd since it will have already been queued into fabric
driver response path code.
Reported-by: Donald White <dew(a)datera.io>
Cc: Donald White <dew(a)datera.io>
Cc: Mike Christie <mchristi(a)redhat.com>
Cc: Hannes Reinecke <hare(a)suse.com>
Signed-off-by: Nicholas Bellinger <nab(a)linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/target/target_core_tmr.c | 9 +++++++++
drivers/target/target_core_transport.c | 2 ++
include/target/target_core_base.h | 1 +
3 files changed, 12 insertions(+)
--- a/drivers/target/target_core_tmr.c
+++ b/drivers/target/target_core_tmr.c
@@ -137,6 +137,15 @@ static bool __target_check_io_state(stru
spin_unlock(&se_cmd->t_state_lock);
return false;
}
+ if (se_cmd->transport_state & CMD_T_PRE_EXECUTE) {
+ if (se_cmd->scsi_status) {
+ pr_debug("Attempted to abort io tag: %u early failure"
+ " status: 0x%02x\n", se_cmd->se_tfo->get_task_tag(se_cmd),
+ se_cmd->scsi_status);
+ spin_unlock(&se_cmd->t_state_lock);
+ return false;
+ }
+ }
if (sess->sess_tearing_down || se_cmd->cmd_wait_set) {
pr_debug("Attempted to abort io tag: %u already shutdown,"
" skipping\n", se_cmd->se_tfo->get_task_tag(se_cmd));
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1796,6 +1796,7 @@ void target_execute_cmd(struct se_cmd *c
}
cmd->t_state = TRANSPORT_PROCESSING;
+ cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
spin_unlock_irq(&cmd->t_state_lock);
/*
@@ -2436,6 +2437,7 @@ int target_get_sess_cmd(struct se_cmd *s
ret = -ESHUTDOWN;
goto out;
}
+ se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
out:
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -538,6 +538,7 @@ struct se_cmd {
#define CMD_T_BUSY (1 << 9)
#define CMD_T_TAS (1 << 10)
#define CMD_T_FABRIC_STOP (1 << 11)
+#define CMD_T_PRE_EXECUTE (1 << 12)
spinlock_t t_state_lock;
struct completion t_transport_stop_comp;
Patches currently in stable-queue which might be from nab(a)linux-iscsi.org are
queue-3.18/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
queue-3.18/target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch
This is a note to let you know that I've just added the patch titled
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From ae072726f6109bb1c94841d6fb3a82dde298ea85 Mon Sep 17 00:00:00 2001
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
Date: Fri, 27 Oct 2017 12:32:59 -0700
Subject: iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
From: Nicholas Bellinger <nab(a)linux-iscsi.org>
commit ae072726f6109bb1c94841d6fb3a82dde298ea85 upstream.
Since commit 59b6986dbf fixed a potential NULL pointer dereference
by allocating a se_tmr_req for ISCSI_TM_FUNC_TASK_REASSIGN, the
se_tmr_req is currently leaked by iscsit_free_cmd() because no
iscsi_cmd->se_cmd.se_tfo was associated.
To address this, treat ISCSI_TM_FUNC_TASK_REASSIGN like any other
TMR and call transport_init_se_cmd() + target_get_sess_cmd() to
setup iscsi_cmd->se_cmd.se_tfo with se_cmd->cmd_kref of 2.
This will ensure normal release operation once se_cmd->cmd_kref
reaches zero and target_release_cmd_kref() is invoked, se_tmr_req
will be released via existing target_free_cmd_mem() and
core_tmr_release_req() code.
Reported-by: Donald White <dew(a)datera.io>
Cc: Donald White <dew(a)datera.io>
Cc: Mike Christie <mchristi(a)redhat.com>
Cc: Hannes Reinecke <hare(a)suse.com>
Signed-off-by: Nicholas Bellinger <nab(a)linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/target/iscsi/iscsi_target.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
--- a/drivers/target/iscsi/iscsi_target.c
+++ b/drivers/target/iscsi/iscsi_target.c
@@ -1750,7 +1750,6 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
struct iscsi_tmr_req *tmr_req;
struct iscsi_tm *hdr;
int out_of_order_cmdsn = 0, ret;
- bool sess_ref = false;
u8 function, tcm_function = TMR_UNKNOWN;
hdr = (struct iscsi_tm *) buf;
@@ -1792,19 +1791,17 @@ iscsit_handle_task_mgt_cmd(struct iscsi_
buf);
}
+ transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
+ conn->sess->se_sess, 0, DMA_NONE,
+ MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
+
+ target_get_sess_cmd(&cmd->se_cmd, true);
+
/*
* TASK_REASSIGN for ERL=2 / connection stays inside of
* LIO-Target $FABRIC_MOD
*/
if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
- transport_init_se_cmd(&cmd->se_cmd,
- &lio_target_fabric_configfs->tf_ops,
- conn->sess->se_sess, 0, DMA_NONE,
- MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
-
- target_get_sess_cmd(&cmd->se_cmd, true);
- sess_ref = true;
-
switch (function) {
case ISCSI_TM_FUNC_ABORT_TASK:
tcm_function = TMR_ABORT_TASK;
@@ -1943,12 +1940,8 @@ attach:
* For connection recovery, this is also the default action for
* TMR TASK_REASSIGN.
*/
- if (sess_ref) {
- pr_debug("Handle TMR, using sess_ref=true check\n");
- target_put_sess_cmd(&cmd->se_cmd);
- }
-
iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
+ target_put_sess_cmd(&cmd->se_cmd);
return 0;
}
EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
Patches currently in stable-queue which might be from nab(a)linux-iscsi.org are
queue-3.18/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
queue-3.18/target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.patch
This is a note to let you know that I've just added the patch titled
bpf, array: fix overflow in max_entries and undefined behavior in index_mask
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
bpf-array-fix-overflow-in-max_entries-and-undefined-behavior-in-index_mask.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From bbeb6e4323dad9b5e0ee9f60c223dd532e2403b1 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel(a)iogearbox.net>
Date: Wed, 10 Jan 2018 23:25:05 +0100
Subject: bpf, array: fix overflow in max_entries and undefined behavior in index_mask
From: Daniel Borkmann <daniel(a)iogearbox.net>
commit bbeb6e4323dad9b5e0ee9f60c223dd532e2403b1 upstream.
syzkaller tried to alloc a map with 0xfffffffd entries out of a userns,
and thus unprivileged. With the recently added logic in b2157399cc98
("bpf: prevent out-of-bounds speculation") we round this up to the next
power of two value for max_entries for unprivileged such that we can
apply proper masking into potentially zeroed out map slots.
However, this will generate an index_mask of 0xffffffff, and therefore
a + 1 will let this overflow into new max_entries of 0. This will pass
allocation, etc, and later on map access we still enforce on the original
attr->max_entries value which was 0xfffffffd, therefore triggering GPF
all over the place. Thus bail out on overflow in such case.
Moreover, on 32 bit archs roundup_pow_of_two() can also not be used,
since fls_long(max_entries - 1) can result in 32 and 1UL << 32 in 32 bit
space is undefined. Therefore, do this by hand in a 64 bit variable.
This fixes all the issues triggered by syzkaller's reproducers.
Fixes: b2157399cc98 ("bpf: prevent out-of-bounds speculation")
Reported-by: syzbot+b0efb8e572d01bce1ae0(a)syzkaller.appspotmail.com
Reported-by: syzbot+6c15e9744f75f2364773(a)syzkaller.appspotmail.com
Reported-by: syzbot+d2f5524fb46fd3b312ee(a)syzkaller.appspotmail.com
Reported-by: syzbot+61d23c95395cc90dbc2b(a)syzkaller.appspotmail.com
Reported-by: syzbot+0d363c942452cca68c01(a)syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast(a)kernel.org>
Cc: Jiri Slaby <jslaby(a)suse.cz>
Cc: Eric Dumazet <eric.dumazet(a)gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
kernel/bpf/arraymap.c | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -53,7 +53,7 @@ static struct bpf_map *array_map_alloc(u
u32 elem_size, index_mask, max_entries;
bool unpriv = !capable(CAP_SYS_ADMIN);
struct bpf_array *array;
- u64 array_size;
+ u64 array_size, mask64;
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
@@ -70,13 +70,25 @@ static struct bpf_map *array_map_alloc(u
elem_size = round_up(attr->value_size, 8);
max_entries = attr->max_entries;
- index_mask = roundup_pow_of_two(max_entries) - 1;
- if (unpriv)
+ /* On 32 bit archs roundup_pow_of_two() with max_entries that has
+ * upper most bit set in u32 space is undefined behavior due to
+ * resulting 1U << 32, so do it manually here in u64 space.
+ */
+ mask64 = fls_long(max_entries - 1);
+ mask64 = 1ULL << mask64;
+ mask64 -= 1;
+
+ index_mask = mask64;
+ if (unpriv) {
/* round up array size to nearest power of 2,
* since cpu will speculate within index_mask limits
*/
max_entries = index_mask + 1;
+ /* Check for overflows. */
+ if (max_entries < attr->max_entries)
+ return ERR_PTR(-E2BIG);
+ }
array_size = sizeof(*array);
if (percpu)
Patches currently in stable-queue which might be from daniel(a)iogearbox.net are
queue-4.14/bpf-array-fix-overflow-in-max_entries-and-undefined-behavior-in-index_mask.patch
queue-4.14/bpf-prevent-out-of-bounds-speculation.patch
queue-4.14/bpf-arsh-is-not-supported-in-32-bit-alu-thus-reject-it.patch
This is a note to let you know that I've just added the patch titled
bpf: arsh is not supported in 32 bit alu thus reject it
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
bpf-arsh-is-not-supported-in-32-bit-alu-thus-reject-it.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 7891a87efc7116590eaba57acc3c422487802c6f Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel(a)iogearbox.net>
Date: Wed, 10 Jan 2018 20:04:37 +0100
Subject: bpf: arsh is not supported in 32 bit alu thus reject it
From: Daniel Borkmann <daniel(a)iogearbox.net>
commit 7891a87efc7116590eaba57acc3c422487802c6f upstream.
The following snippet was throwing an 'unknown opcode cc' warning
in BPF interpreter:
0: (18) r0 = 0x0
2: (7b) *(u64 *)(r10 -16) = r0
3: (cc) (u32) r0 s>>= (u32) r0
4: (95) exit
Although a number of JITs do support BPF_ALU | BPF_ARSH | BPF_{K,X}
generation, not all of them do and interpreter does neither. We can
leave existing ones and implement it later in bpf-next for the
remaining ones, but reject this properly in verifier for the time
being.
Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)")
Reported-by: syzbot+93c4904c5c70348a6890(a)syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
kernel/bpf/verifier.c | 5 +++
tools/testing/selftests/bpf/test_verifier.c | 40 ++++++++++++++++++++++++++++
2 files changed, 45 insertions(+)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2493,6 +2493,11 @@ static int check_alu_op(struct bpf_verif
return -EINVAL;
}
+ if (opcode == BPF_ARSH && BPF_CLASS(insn->code) != BPF_ALU64) {
+ verbose("BPF_ARSH not supported for 32 bit ALU\n");
+ return -EINVAL;
+ }
+
if ((opcode == BPF_LSH || opcode == BPF_RSH ||
opcode == BPF_ARSH) && BPF_SRC(insn->code) == BPF_K) {
int size = BPF_CLASS(insn->code) == BPF_ALU64 ? 64 : 32;
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -273,6 +273,46 @@ static struct bpf_test tests[] = {
.result = REJECT,
},
{
+ "arsh32 on imm",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_ALU32_IMM(BPF_ARSH, BPF_REG_0, 5),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ .errstr = "BPF_ARSH not supported for 32 bit ALU",
+ },
+ {
+ "arsh32 on reg",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_MOV64_IMM(BPF_REG_1, 5),
+ BPF_ALU32_REG(BPF_ARSH, BPF_REG_0, BPF_REG_1),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ .errstr = "BPF_ARSH not supported for 32 bit ALU",
+ },
+ {
+ "arsh64 on imm",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_ALU64_IMM(BPF_ARSH, BPF_REG_0, 5),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
+ "arsh64 on reg",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_MOV64_IMM(BPF_REG_1, 5),
+ BPF_ALU64_REG(BPF_ARSH, BPF_REG_0, BPF_REG_1),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
"no bpf_exit",
.insns = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_0, BPF_REG_2),
Patches currently in stable-queue which might be from daniel(a)iogearbox.net are
queue-4.14/bpf-array-fix-overflow-in-max_entries-and-undefined-behavior-in-index_mask.patch
queue-4.14/bpf-prevent-out-of-bounds-speculation.patch
queue-4.14/bpf-arsh-is-not-supported-in-32-bit-alu-thus-reject-it.patch
This is a note to let you know that I've just added the patch titled
bpf: refactor fixup_bpf_calls()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
bpf-refactor-fixup_bpf_calls.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 79741b3bdec01a8628368fbcfccc7d189ed606cb Mon Sep 17 00:00:00 2001
From: Alexei Starovoitov <ast(a)fb.com>
Date: Wed, 15 Mar 2017 18:26:40 -0700
Subject: bpf: refactor fixup_bpf_calls()
From: Alexei Starovoitov <ast(a)fb.com>
commit 79741b3bdec01a8628368fbcfccc7d189ed606cb upstream.
reduce indent and make it iterate over instructions similar to
convert_ctx_accesses(). Also convert hard BUG_ON into soft verifier error.
Signed-off-by: Alexei Starovoitov <ast(a)kernel.org>
Acked-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Cc: Jiri Slaby <jslaby(a)suse.cz>
[Backported to 4.9.y - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
kernel/bpf/verifier.c | 75 +++++++++++++++++++++++---------------------------
1 file changed, 35 insertions(+), 40 deletions(-)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3362,55 +3362,50 @@ static int convert_ctx_accesses(struct b
return 0;
}
-/* fixup insn->imm field of bpf_call instructions:
- * if (insn->imm == BPF_FUNC_map_lookup_elem)
- * insn->imm = bpf_map_lookup_elem - __bpf_call_base;
- * else if (insn->imm == BPF_FUNC_map_update_elem)
- * insn->imm = bpf_map_update_elem - __bpf_call_base;
- * else ...
+/* fixup insn->imm field of bpf_call instructions
*
* this function is called after eBPF program passed verification
*/
-static void fixup_bpf_calls(struct bpf_prog *prog)
+static int fixup_bpf_calls(struct bpf_verifier_env *env)
{
+ struct bpf_prog *prog = env->prog;
+ struct bpf_insn *insn = prog->insnsi;
const struct bpf_func_proto *fn;
+ const int insn_cnt = prog->len;
int i;
- for (i = 0; i < prog->len; i++) {
- struct bpf_insn *insn = &prog->insnsi[i];
-
- if (insn->code == (BPF_JMP | BPF_CALL)) {
- /* we reach here when program has bpf_call instructions
- * and it passed bpf_check(), means that
- * ops->get_func_proto must have been supplied, check it
- */
- BUG_ON(!prog->aux->ops->get_func_proto);
-
- if (insn->imm == BPF_FUNC_get_route_realm)
- prog->dst_needed = 1;
- if (insn->imm == BPF_FUNC_get_prandom_u32)
- bpf_user_rnd_init_once();
- if (insn->imm == BPF_FUNC_tail_call) {
- /* mark bpf_tail_call as different opcode
- * to avoid conditional branch in
- * interpeter for every normal call
- * and to prevent accidental JITing by
- * JIT compiler that doesn't support
- * bpf_tail_call yet
- */
- insn->imm = 0;
- insn->code |= BPF_X;
- continue;
- }
+ for (i = 0; i < insn_cnt; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL))
+ continue;
+
+ if (insn->imm == BPF_FUNC_get_route_realm)
+ prog->dst_needed = 1;
+ if (insn->imm == BPF_FUNC_get_prandom_u32)
+ bpf_user_rnd_init_once();
+ if (insn->imm == BPF_FUNC_tail_call) {
+ /* mark bpf_tail_call as different opcode to avoid
+ * conditional branch in the interpeter for every normal
+ * call and to prevent accidental JITing by JIT compiler
+ * that doesn't support bpf_tail_call yet
+ */
+ insn->imm = 0;
+ insn->code |= BPF_X;
+ continue;
+ }
- fn = prog->aux->ops->get_func_proto(insn->imm);
- /* all functions that have prototype and verifier allowed
- * programs to call them, must be real in-kernel functions
- */
- BUG_ON(!fn->func);
- insn->imm = fn->func - __bpf_call_base;
+ fn = prog->aux->ops->get_func_proto(insn->imm);
+ /* all functions that have prototype and verifier allowed
+ * programs to call them, must be real in-kernel functions
+ */
+ if (!fn->func) {
+ verbose("kernel subsystem misconfigured func %d\n",
+ insn->imm);
+ return -EFAULT;
}
+ insn->imm = fn->func - __bpf_call_base;
}
+
+ return 0;
}
static void free_states(struct bpf_verifier_env *env)
@@ -3515,7 +3510,7 @@ skip_full_check:
ret = convert_ctx_accesses(env);
if (ret == 0)
- fixup_bpf_calls(env->prog);
+ ret = fixup_bpf_calls(env);
if (log_level && log_len >= log_size - 1) {
BUG_ON(log_len >= log_size);
Patches currently in stable-queue which might be from ast(a)fb.com are
queue-4.9/bpf-refactor-fixup_bpf_calls.patch
queue-4.9/bpf-move-fixup_bpf_calls-function.patch