This is a note to let you know that I've just added the patch titled
MIPS: Factor out NT_PRFPREG regset access helpers
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:
mips-factor-out-nt_prfpreg-regset-access-helpers.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 a03fe72572c12e98f4173f8a535f32468e48b6ec Mon Sep 17 00:00:00 2001
From: "Maciej W. Rozycki" <macro(a)mips.com>
Date: Mon, 11 Dec 2017 22:51:35 +0000
Subject: MIPS: Factor out NT_PRFPREG regset access helpers
From: Maciej W. Rozycki <macro(a)mips.com>
commit a03fe72572c12e98f4173f8a535f32468e48b6ec upstream.
In preparation to fix a commit 72b22bbad1e7 ("MIPS: Don't assume 64-bit
FP registers for FP regset") FCSR access regression factor out
NT_PRFPREG regset access helpers for the non-MSA and the MSA variants
respectively, to avoid having to deal with excessive indentation in the
actual fix.
No functional change, however use `target->thread.fpu.fpr[0]' rather
than `target->thread.fpu.fpr[i]' for FGR holding type size determination
as there's no `i' variable to refer to anymore, and for the factored out
`i' variable declaration use `unsigned int' rather than `unsigned' as
its type, following the common style.
Signed-off-by: Maciej W. Rozycki <macro(a)mips.com>
Fixes: 72b22bbad1e7 ("MIPS: Don't assume 64-bit FP registers for FP regset")
Cc: James Hogan <james.hogan(a)mips.com>
Cc: Paul Burton <Paul.Burton(a)mips.com>
Cc: Alex Smith <alex(a)alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin(a)arm.com>
Cc: linux-mips(a)linux-mips.org
Cc: linux-kernel(a)vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17925/
Signed-off-by: Ralf Baechle <ralf(a)linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/kernel/ptrace.c | 106 +++++++++++++++++++++++++++++++++++-----------
1 file changed, 82 insertions(+), 24 deletions(-)
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -400,25 +400,36 @@ static int gpr64_set(struct task_struct
#endif /* CONFIG_64BIT */
-static int fpr_get(struct task_struct *target,
- const struct user_regset *regset,
- unsigned int pos, unsigned int count,
- void *kbuf, void __user *ubuf)
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer,
+ * !CONFIG_CPU_HAS_MSA variant. FP context's general register slots
+ * correspond 1:1 to buffer slots.
+ */
+static int fpr_get_fpa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ void **kbuf, void __user **ubuf)
{
- unsigned i;
- int err;
- u64 fpr_val;
-
- /* XXX fcr31 */
+ return user_regset_copyout(pos, count, kbuf, ubuf,
+ &target->thread.fpu,
+ 0, sizeof(elf_fpregset_t));
+}
- if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
- return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
- &target->thread.fpu,
- 0, sizeof(elf_fpregset_t));
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer,
+ * CONFIG_CPU_HAS_MSA variant. Only lower 64 bits of FP context's
+ * general register slots are copied to buffer slots.
+ */
+static int fpr_get_msa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ void **kbuf, void __user **ubuf)
+{
+ unsigned int i;
+ u64 fpr_val;
+ int err;
for (i = 0; i < NUM_FPU_REGS; i++) {
fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
- err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ err = user_regset_copyout(pos, count, kbuf, ubuf,
&fpr_val, i * sizeof(elf_fpreg_t),
(i + 1) * sizeof(elf_fpreg_t));
if (err)
@@ -428,25 +439,54 @@ static int fpr_get(struct task_struct *t
return 0;
}
-static int fpr_set(struct task_struct *target,
+/* Copy the floating-point context to the supplied NT_PRFPREG buffer. */
+static int fpr_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
- const void *kbuf, const void __user *ubuf)
+ void *kbuf, void __user *ubuf)
{
- unsigned i;
int err;
- u64 fpr_val;
/* XXX fcr31 */
- if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
- return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
- &target->thread.fpu,
- 0, sizeof(elf_fpregset_t));
+ if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+ err = fpr_get_fpa(target, &pos, &count, &kbuf, &ubuf);
+ else
+ err = fpr_get_msa(target, &pos, &count, &kbuf, &ubuf);
+
+ return err;
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context,
+ * !CONFIG_CPU_HAS_MSA variant. Buffer slots correspond 1:1 to FP
+ * context's general register slots.
+ */
+static int fpr_set_fpa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ const void **kbuf, const void __user **ubuf)
+{
+ return user_regset_copyin(pos, count, kbuf, ubuf,
+ &target->thread.fpu,
+ 0, sizeof(elf_fpregset_t));
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context,
+ * CONFIG_CPU_HAS_MSA variant. Buffer slots are copied to lower 64
+ * bits only of FP context's general register slots.
+ */
+static int fpr_set_msa(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ const void **kbuf, const void __user **ubuf)
+{
+ unsigned int i;
+ u64 fpr_val;
+ int err;
BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
- for (i = 0; i < NUM_FPU_REGS && count >= sizeof(elf_fpreg_t); i++) {
- err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ for (i = 0; i < NUM_FPU_REGS && *count >= sizeof(elf_fpreg_t); i++) {
+ err = user_regset_copyin(pos, count, kbuf, ubuf,
&fpr_val, i * sizeof(elf_fpreg_t),
(i + 1) * sizeof(elf_fpreg_t));
if (err)
@@ -457,6 +497,24 @@ static int fpr_set(struct task_struct *t
return 0;
}
+/* Copy the supplied NT_PRFPREG buffer to the floating-point context. */
+static int fpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int err;
+
+ /* XXX fcr31 */
+
+ if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+ err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);
+ else
+ err = fpr_set_msa(target, &pos, &count, &kbuf, &ubuf);
+
+ return err;
+}
+
enum mips_regset {
REGSET_GPR,
REGSET_FPR,
Patches currently in stable-queue which might be from macro(a)mips.com are
queue-3.18/mips-consistently-handle-buffer-counter-with-ptrace_setregset.patch
queue-3.18/mips-disallow-outsized-ptrace_setregset-nt_prfpreg-regset-accesses.patch
queue-3.18/mips-guard-against-any-partial-write-attempt-with-ptrace_setregset.patch
queue-3.18/mips-also-verify-sizeof-elf_fpreg_t-with-ptrace_setregset.patch
queue-3.18/mips-factor-out-nt_prfpreg-regset-access-helpers.patch
queue-3.18/mips-fix-an-fcsr-access-api-regression-with-nt_prfpreg-and-msa.patch
This is a note to let you know that I've just added the patch titled
MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses
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:
mips-disallow-outsized-ptrace_setregset-nt_prfpreg-regset-accesses.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 c8c5a3a24d395b14447a9a89d61586a913840a3b Mon Sep 17 00:00:00 2001
From: "Maciej W. Rozycki" <macro(a)mips.com>
Date: Mon, 11 Dec 2017 22:56:54 +0000
Subject: MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses
From: Maciej W. Rozycki <macro(a)mips.com>
commit c8c5a3a24d395b14447a9a89d61586a913840a3b upstream.
Complement commit c23b3d1a5311 ("MIPS: ptrace: Change GP regset to use
correct core dump register layout") and also reject outsized
PTRACE_SETREGSET requests to the NT_PRFPREG regset, like with the
NT_PRSTATUS regset.
Signed-off-by: Maciej W. Rozycki <macro(a)mips.com>
Fixes: c23b3d1a5311 ("MIPS: ptrace: Change GP regset to use correct core dump register layout")
Cc: James Hogan <james.hogan(a)mips.com>
Cc: Paul Burton <Paul.Burton(a)mips.com>
Cc: Alex Smith <alex(a)alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin(a)arm.com>
Cc: linux-mips(a)linux-mips.org
Cc: linux-kernel(a)vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17930/
Signed-off-by: Ralf Baechle <ralf(a)linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/kernel/ptrace.c | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -530,6 +530,9 @@ static int fpr_set(struct task_struct *t
BUG_ON(count % sizeof(elf_fpreg_t));
+ if (pos + count > sizeof(elf_fpregset_t))
+ return -EIO;
+
if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);
else
Patches currently in stable-queue which might be from macro(a)mips.com are
queue-3.18/mips-consistently-handle-buffer-counter-with-ptrace_setregset.patch
queue-3.18/mips-disallow-outsized-ptrace_setregset-nt_prfpreg-regset-accesses.patch
queue-3.18/mips-guard-against-any-partial-write-attempt-with-ptrace_setregset.patch
queue-3.18/mips-also-verify-sizeof-elf_fpreg_t-with-ptrace_setregset.patch
queue-3.18/mips-factor-out-nt_prfpreg-regset-access-helpers.patch
queue-3.18/mips-fix-an-fcsr-access-api-regression-with-nt_prfpreg-and-msa.patch
This is a note to let you know that I've just added the patch titled
MIPS: Consistently handle buffer counter with PTRACE_SETREGSET
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:
mips-consistently-handle-buffer-counter-with-ptrace_setregset.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 80b3ffce0196ea50068885d085ff981e4b8396f4 Mon Sep 17 00:00:00 2001
From: "Maciej W. Rozycki" <macro(a)mips.com>
Date: Mon, 11 Dec 2017 22:53:14 +0000
Subject: MIPS: Consistently handle buffer counter with PTRACE_SETREGSET
From: Maciej W. Rozycki <macro(a)mips.com>
commit 80b3ffce0196ea50068885d085ff981e4b8396f4 upstream.
Update commit d614fd58a283 ("mips/ptrace: Preserve previous registers
for short regset write") bug and consistently consume all data supplied
to `fpr_set_msa' with the ptrace(2) PTRACE_SETREGSET request, such that
a zero data buffer counter is returned where insufficient data has been
given to fill a whole number of FP general registers.
In reality this is not going to happen, as the caller is supposed to
only supply data covering a whole number of registers and it is verified
in `ptrace_regset' and again asserted in `fpr_set', however structuring
code such that the presence of trailing partial FP general register data
causes `fpr_set_msa' to return with a non-zero data buffer counter makes
it appear that this trailing data will be used if there are subsequent
writes made to FP registers, which is going to be the case with the FCSR
once the missing write to that register has been fixed.
Fixes: d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write")
Signed-off-by: Maciej W. Rozycki <macro(a)mips.com>
Cc: James Hogan <james.hogan(a)mips.com>
Cc: Paul Burton <Paul.Burton(a)mips.com>
Cc: Alex Smith <alex(a)alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin(a)arm.com>
Cc: linux-mips(a)linux-mips.org
Cc: linux-kernel(a)vger.kernel.org
Cc: stable(a)vger.kernel.org # v4.11+
Patchwork: https://patchwork.linux-mips.org/patch/17927/
Signed-off-by: Ralf Baechle <ralf(a)linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/kernel/ptrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -485,7 +485,7 @@ static int fpr_set_msa(struct task_struc
int err;
BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
- for (i = 0; i < NUM_FPU_REGS && *count >= sizeof(elf_fpreg_t); i++) {
+ for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) {
err = user_regset_copyin(pos, count, kbuf, ubuf,
&fpr_val, i * sizeof(elf_fpreg_t),
(i + 1) * sizeof(elf_fpreg_t));
Patches currently in stable-queue which might be from macro(a)mips.com are
queue-3.18/mips-consistently-handle-buffer-counter-with-ptrace_setregset.patch
queue-3.18/mips-disallow-outsized-ptrace_setregset-nt_prfpreg-regset-accesses.patch
queue-3.18/mips-guard-against-any-partial-write-attempt-with-ptrace_setregset.patch
queue-3.18/mips-also-verify-sizeof-elf_fpreg_t-with-ptrace_setregset.patch
queue-3.18/mips-factor-out-nt_prfpreg-regset-access-helpers.patch
queue-3.18/mips-fix-an-fcsr-access-api-regression-with-nt_prfpreg-and-msa.patch
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 4.9-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:
target-avoid-early-cmd_t_pre_execute-failures-during-abort_task.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 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
@@ -1939,6 +1939,7 @@ 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);
@@ -2592,6 +2593,7 @@ 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
@@ -493,6 +493,7 @@ 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-4.9/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
queue-4.9/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 4.9-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:
iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.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 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
@@ -1940,7 +1940,6 @@ 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;
@@ -1982,18 +1981,17 @@ 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;
@@ -2132,12 +2130,8 @@ 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-4.9/iscsi-target-make-task_reassign-use-proper-se_cmd-cmd_kref.patch
queue-4.9/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 v4.9.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