--- /dev/null
+From stable+bounces-6807-greg=kroah.com@vger.kernel.org Fri Dec 15 12:17:59 2023
+From: Naveen N Rao <naveen@kernel.org>
+Date: Fri, 15 Dec 2023 16:44:32 +0530
+Subject: powerpc/ftrace: Create a dummy stackframe to fix stack unwind
+To: <stable@vger.kernel.org>
+Cc: Greg KH <gregkh@linuxfoundation.org>, Michael Ellerman <mpe@ellerman.id.au>
+Message-ID: <20231215111433.2362641-1-naveen@kernel.org>
+
+From: Naveen N Rao <naveen@kernel.org>
+
+commit 41a506ef71eb38d94fe133f565c87c3e06ccc072 upstream.
+
+With ppc64 -mprofile-kernel and ppc32 -pg, profiling instructions to
+call into ftrace are emitted right at function entry. The instruction
+sequence used is minimal to reduce overhead. Crucially, a stackframe is
+not created for the function being traced. This breaks stack unwinding
+since the function being traced does not have a stackframe for itself.
+As such, it never shows up in the backtrace:
+
+/sys/kernel/debug/tracing # echo 1 > /proc/sys/kernel/stack_tracer_enabled
+/sys/kernel/debug/tracing # cat stack_trace
+ Depth Size Location (17 entries)
+ ----- ---- --------
+ 0) 4144 32 ftrace_call+0x4/0x44
+ 1) 4112 432 get_page_from_freelist+0x26c/0x1ad0
+ 2) 3680 496 __alloc_pages+0x290/0x1280
+ 3) 3184 336 __folio_alloc+0x34/0x90
+ 4) 2848 176 vma_alloc_folio+0xd8/0x540
+ 5) 2672 272 __handle_mm_fault+0x700/0x1cc0
+ 6) 2400 208 handle_mm_fault+0xf0/0x3f0
+ 7) 2192 80 ___do_page_fault+0x3e4/0xbe0
+ 8) 2112 160 do_page_fault+0x30/0xc0
+ 9) 1952 256 data_access_common_virt+0x210/0x220
+ 10) 1696 400 0xc00000000f16b100
+ 11) 1296 384 load_elf_binary+0x804/0x1b80
+ 12) 912 208 bprm_execve+0x2d8/0x7e0
+ 13) 704 64 do_execveat_common+0x1d0/0x2f0
+ 14) 640 160 sys_execve+0x54/0x70
+ 15) 480 64 system_call_exception+0x138/0x350
+ 16) 416 416 system_call_common+0x160/0x2c4
+
+Fix this by having ftrace create a dummy stackframe for the function
+being traced. With this, backtraces now capture the function being
+traced:
+
+/sys/kernel/debug/tracing # cat stack_trace
+ Depth Size Location (17 entries)
+ ----- ---- --------
+ 0) 3888 32 _raw_spin_trylock+0x8/0x70
+ 1) 3856 576 get_page_from_freelist+0x26c/0x1ad0
+ 2) 3280 64 __alloc_pages+0x290/0x1280
+ 3) 3216 336 __folio_alloc+0x34/0x90
+ 4) 2880 176 vma_alloc_folio+0xd8/0x540
+ 5) 2704 416 __handle_mm_fault+0x700/0x1cc0
+ 6) 2288 96 handle_mm_fault+0xf0/0x3f0
+ 7) 2192 48 ___do_page_fault+0x3e4/0xbe0
+ 8) 2144 192 do_page_fault+0x30/0xc0
+ 9) 1952 608 data_access_common_virt+0x210/0x220
+ 10) 1344 16 0xc0000000334bbb50
+ 11) 1328 416 load_elf_binary+0x804/0x1b80
+ 12) 912 64 bprm_execve+0x2d8/0x7e0
+ 13) 848 176 do_execveat_common+0x1d0/0x2f0
+ 14) 672 192 sys_execve+0x54/0x70
+ 15) 480 64 system_call_exception+0x138/0x350
+ 16) 416 416 system_call_common+0x160/0x2c4
+
+This results in two additional stores in the ftrace entry code, but
+produces reliable backtraces.
+
+Fixes: 153086644fd1 ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI")
+Cc: stable@vger.kernel.org
+Signed-off-by: Naveen N Rao <naveen@kernel.org>
+Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
+Link: https://msgid.link/20230621051349.759567-1-naveen@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 13 +++++++++++--
+ 1 file changed, 11 insertions(+), 2 deletions(-)
+
+--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
++++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+@@ -36,6 +36,9 @@ _GLOBAL(ftrace_regs_caller)
+ /* Save the original return address in A's stack frame */
+ std r0,LRSAVE(r1)
+
++ /* Create a minimal stack frame for representing B */
++ stdu r1, -STACK_FRAME_MIN_SIZE(r1)
++
+ /* Create our stack frame + pt_regs */
+ stdu r1,-SWITCH_FRAME_SIZE(r1)
+
+@@ -65,6 +68,8 @@ _GLOBAL(ftrace_regs_caller)
+ mflr r7
+ /* Save it as pt_regs->nip */
+ std r7, _NIP(r1)
++ /* Also save it in B's stackframe header for proper unwind */
++ std r7, LRSAVE+SWITCH_FRAME_SIZE(r1)
+ /* Save the read LR in pt_regs->link */
+ std r0, _LINK(r1)
+
+@@ -121,7 +126,7 @@ ftrace_regs_call:
+ ld r2, 24(r1)
+
+ /* Pop our stack frame */
+- addi r1, r1, SWITCH_FRAME_SIZE
++ addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+
+ #ifdef CONFIG_LIVEPATCH
+ /* Based on the cmpd above, if the NIP was altered handle livepatch */
+@@ -153,6 +158,9 @@ _GLOBAL(ftrace_caller)
+ /* Save the original return address in A's stack frame */
+ std r0, LRSAVE(r1)
+
++ /* Create a minimal stack frame for representing B */
++ stdu r1, -STACK_FRAME_MIN_SIZE(r1)
++
+ /* Create our stack frame + pt_regs */
+ stdu r1, -SWITCH_FRAME_SIZE(r1)
+
+@@ -166,6 +174,7 @@ _GLOBAL(ftrace_caller)
+ /* Get the _mcount() call site out of LR */
+ mflr r7
+ std r7, _NIP(r1)
++ std r7, LRSAVE+SWITCH_FRAME_SIZE(r1)
+
+ /* Save callee's TOC in the ABI compliant location */
+ std r2, 24(r1)
+@@ -200,7 +209,7 @@ ftrace_call:
+ ld r2, 24(r1)
+
+ /* Pop our stack frame */
+- addi r1, r1, SWITCH_FRAME_SIZE
++ addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+
+ /* Reload original LR */
+ ld r0, LRSAVE(r1)
--- /dev/null
+From stable+bounces-6808-greg=kroah.com@vger.kernel.org Fri Dec 15 12:18:31 2023
+From: Naveen N Rao <naveen@kernel.org>
+Date: Fri, 15 Dec 2023 16:44:33 +0530
+Subject: powerpc/ftrace: Fix stack teardown in ftrace_no_trace
+To: <stable@vger.kernel.org>
+Cc: Greg KH <gregkh@linuxfoundation.org>, Michael Ellerman <mpe@ellerman.id.au>
+Message-ID: <20231215111433.2362641-2-naveen@kernel.org>
+
+From: Naveen N Rao <naveen@kernel.org>
+
+commit 4b3338aaa74d7d4ec5b6734dc298f0db94ec83d2 upstream.
+
+Commit 41a506ef71eb ("powerpc/ftrace: Create a dummy stackframe to fix
+stack unwind") added use of a new stack frame on ftrace entry to fix
+stack unwind. However, the commit missed updating the offset used while
+tearing down the ftrace stack when ftrace is disabled. Fix the same.
+
+In addition, the commit missed saving the correct stack pointer in
+pt_regs. Update the same.
+
+Fixes: 41a506ef71eb ("powerpc/ftrace: Create a dummy stackframe to fix stack unwind")
+Cc: stable@vger.kernel.org # v6.5+
+Signed-off-by: Naveen N Rao <naveen@kernel.org>
+Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
+Link: https://msgid.link/20231130065947.2188860-1-naveen@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
++++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+@@ -55,7 +55,7 @@ _GLOBAL(ftrace_regs_caller)
+ SAVE_10GPRS(22, r1)
+
+ /* Save previous stack pointer (r1) */
+- addi r8, r1, SWITCH_FRAME_SIZE
++ addi r8, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+ std r8, GPR1(r1)
+
+ /* Load special regs for save below */
+@@ -150,7 +150,7 @@ ftrace_no_trace:
+ mflr r3
+ mtctr r3
+ REST_GPR(3, r1)
+- addi r1, r1, SWITCH_FRAME_SIZE
++ addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+ mtlr r0
+ bctr
+
ring-buffer-fix-writing-to-the-buffer-with-max_data_size.patch
ring-buffer-fix-a-race-in-rb_time_cmpxchg-for-32-bit-archs.patch
usb-gadget-core-adjust-uevent-timing-on-gadget-unbind.patch
+tty-n_gsm-fix-tty-registration-before-control-channel-open.patch
+tty-n_gsm-remove-duplicates-of-parameters.patch
+tty-n_gsm-add-sanity-check-for-gsm-receive-in-gsm_receive_buf.patch
+powerpc-ftrace-create-a-dummy-stackframe-to-fix-stack-unwind.patch
+powerpc-ftrace-fix-stack-teardown-in-ftrace_no_trace.patch
--- /dev/null
+From Ilia.Gavrilov@infotecs.ru Tue Dec 12 12:17:23 2023
+From: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
+Date: Tue, 12 Dec 2023 11:17:21 +0000
+Subject: tty: n_gsm: add sanity check for gsm->receive in gsm_receive_buf()
+To: "stable@vger.kernel.org" <stable@vger.kernel.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Cc: Daniel Starke <daniel.starke@siemens.com>, Jiri Slaby <jirislaby@kernel.org>, Russ Gorby <russ.gorby@intel.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "lvc-project@linuxtesting.org" <lvc-project@linuxtesting.org>, "syzbot+e3563f0c94e188366dbb@syzkaller.appspotmail.com" <syzbot+e3563f0c94e188366dbb@syzkaller.appspotmail.com>, Mazin Al Haddad <mazinalhaddad05@gmail.com>
+Message-ID: <20231212111431.4064760-4-Ilia.Gavrilov@infotecs.ru>
+
+From: Mazin Al Haddad <mazinalhaddad05@gmail.com>
+
+commit f16c6d2e58a4c2b972efcf9eb12390ee0ba3befb upstream
+
+A null pointer dereference can happen when attempting to access the
+"gsm->receive()" function in gsmld_receive_buf(). Currently, the code
+assumes that gsm->receive is only called after MUX activation.
+Since the gsmld_receive_buf() function can be accessed without the need to
+initialize the MUX, the gsm->receive() function will not be set and a
+NULL pointer dereference will occur.
+
+Fix this by avoiding the call to "gsm->receive()" in case the function is
+not initialized by adding a sanity check.
+
+Call Trace:
+ <TASK>
+ gsmld_receive_buf+0x1c2/0x2f0 drivers/tty/n_gsm.c:2861
+ tiocsti drivers/tty/tty_io.c:2293 [inline]
+ tty_ioctl+0xa75/0x15d0 drivers/tty/tty_io.c:2692
+ vfs_ioctl fs/ioctl.c:51 [inline]
+ __do_sys_ioctl fs/ioctl.c:870 [inline]
+ __se_sys_ioctl fs/ioctl.c:856 [inline]
+ __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
+ do_syscall_x64 arch/x86/entry/common.c:50 [inline]
+ do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
+ entry_SYSCALL_64_after_hwframe+0x63/0xcd
+
+Link: https://syzkaller.appspot.com/bug?id=bdf035c61447f8c6e0e6920315d577cb5cc35ac5
+Fixes: 01aecd917114 ("tty: n_gsm: fix tty registration before control channel open")
+Reported-and-tested-by: syzbot+e3563f0c94e188366dbb@syzkaller.appspotmail.com
+Signed-off-by: Mazin Al Haddad <mazinalhaddad05@gmail.com>
+Link: https://lore.kernel.org/r/20220814015211.84180-1-mazinalhaddad05@gmail.com
+Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/n_gsm.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/drivers/tty/n_gsm.c
++++ b/drivers/tty/n_gsm.c
+@@ -2588,7 +2588,8 @@ static void gsmld_receive_buf(struct tty
+ flags = *fp++;
+ switch (flags) {
+ case TTY_NORMAL:
+- gsm->receive(gsm, *cp);
++ if (gsm->receive)
++ gsm->receive(gsm, *cp);
+ break;
+ case TTY_OVERRUN:
+ case TTY_BREAK:
--- /dev/null
+From Ilia.Gavrilov@infotecs.ru Tue Dec 12 12:17:22 2023
+From: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
+Date: Tue, 12 Dec 2023 11:17:21 +0000
+Subject: tty: n_gsm: fix tty registration before control channel open
+To: "stable@vger.kernel.org" <stable@vger.kernel.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Cc: Daniel Starke <daniel.starke@siemens.com>, Jiri Slaby <jirislaby@kernel.org>, Russ Gorby <russ.gorby@intel.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "lvc-project@linuxtesting.org" <lvc-project@linuxtesting.org>
+Message-ID: <20231212111431.4064760-2-Ilia.Gavrilov@infotecs.ru>
+
+From: Daniel Starke <daniel.starke@siemens.com>
+
+commit 01aecd917114577c423f07cec0d186ad007d76fc upstream.
+
+The current implementation registers/deregisters the user ttys at mux
+attach/detach. That means that the user devices are available before any
+control channel is open. However, user channel initialization requires an
+open control channel. Furthermore, the user is not informed if the mux
+restarts due to configuration changes.
+Put the registration/deregistration procedure into separate function to
+improve readability.
+Move registration to mux activation and deregistration to mux cleanup to
+keep the user devices only open as long as a control channel exists. The
+user will be informed via the device driver if the mux was reconfigured in
+a way that required a mux re-activation.
+This makes it necessary to add T2 initialization to gsmld_open() for the
+ldisc open code path (not the reconfiguration code path) to avoid deletion
+of an uninitialized T2 at mux cleanup.
+
+Fixes: d50f6dcaf22a ("tty: n_gsm: expose gsmtty device nodes at ldisc open time")
+Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
+Link: https://lore.kernel.org/r/20220701061652.39604-2-daniel.starke@siemens.com
+Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/n_gsm.c | 117 +++++++++++++++++++++++++++++++++++-----------------
+ 1 file changed, 79 insertions(+), 38 deletions(-)
+
+--- a/drivers/tty/n_gsm.c
++++ b/drivers/tty/n_gsm.c
+@@ -235,6 +235,7 @@ struct gsm_mux {
+ struct gsm_dlci *dlci[NUM_DLCI];
+ int old_c_iflag; /* termios c_iflag value before attach */
+ bool constipated; /* Asked by remote to shut up */
++ bool has_devices; /* Devices were registered */
+
+ spinlock_t tx_lock;
+ unsigned int tx_bytes; /* TX data outstanding */
+@@ -465,6 +466,68 @@ static u8 gsm_encode_modem(const struct
+ }
+
+ /**
++ * gsm_register_devices - register all tty devices for a given mux index
++ *
++ * @driver: the tty driver that describes the tty devices
++ * @index: the mux number is used to calculate the minor numbers of the
++ * ttys for this mux and may differ from the position in the
++ * mux array.
++ */
++static int gsm_register_devices(struct tty_driver *driver, unsigned int index)
++{
++ struct device *dev;
++ int i;
++ unsigned int base;
++
++ if (!driver || index >= MAX_MUX)
++ return -EINVAL;
++
++ base = index * NUM_DLCI; /* first minor for this index */
++ for (i = 1; i < NUM_DLCI; i++) {
++ /* Don't register device 0 - this is the control channel
++ * and not a usable tty interface
++ */
++ dev = tty_register_device(gsm_tty_driver, base + i, NULL);
++ if (IS_ERR(dev)) {
++ if (debug & 8)
++ pr_info("%s failed to register device minor %u",
++ __func__, base + i);
++ for (i--; i >= 1; i--)
++ tty_unregister_device(gsm_tty_driver, base + i);
++ return PTR_ERR(dev);
++ }
++ }
++
++ return 0;
++}
++
++/**
++ * gsm_unregister_devices - unregister all tty devices for a given mux index
++ *
++ * @driver: the tty driver that describes the tty devices
++ * @index: the mux number is used to calculate the minor numbers of the
++ * ttys for this mux and may differ from the position in the
++ * mux array.
++ */
++static void gsm_unregister_devices(struct tty_driver *driver,
++ unsigned int index)
++{
++ int i;
++ unsigned int base;
++
++ if (!driver || index >= MAX_MUX)
++ return;
++
++ base = index * NUM_DLCI; /* first minor for this index */
++ for (i = 1; i < NUM_DLCI; i++) {
++ /* Don't unregister device 0 - this is the control
++ * channel and not a usable tty interface
++ */
++ tty_unregister_device(gsm_tty_driver, base + i);
++ }
++}
++
++/**
+ * gsm_print_packet - display a frame for debug
+ * @hdr: header to print before decode
+ * @addr: address EA from the frame
+@@ -2178,6 +2241,10 @@ static void gsm_cleanup_mux(struct gsm_m
+ del_timer_sync(&gsm->t2_timer);
+
+ /* Free up any link layer users and finally the control channel */
++ if (gsm->has_devices) {
++ gsm_unregister_devices(gsm_tty_driver, gsm->num);
++ gsm->has_devices = false;
++ }
+ for (i = NUM_DLCI - 1; i >= 0; i--)
+ if (gsm->dlci[i])
+ gsm_dlci_release(gsm->dlci[i]);
+@@ -2201,15 +2268,21 @@ static void gsm_cleanup_mux(struct gsm_m
+ static int gsm_activate_mux(struct gsm_mux *gsm)
+ {
+ struct gsm_dlci *dlci;
++ int ret;
+
+ if (gsm->encoding == 0)
+ gsm->receive = gsm0_receive;
+ else
+ gsm->receive = gsm1_receive;
+
++ ret = gsm_register_devices(gsm_tty_driver, gsm->num);
++ if (ret)
++ return ret;
++
+ dlci = gsm_dlci_alloc(gsm, 0);
+ if (dlci == NULL)
+ return -ENOMEM;
++ gsm->has_devices = true;
+ gsm->dead = false; /* Tty opens are now permissible */
+ return 0;
+ }
+@@ -2475,39 +2548,14 @@ static int gsmld_output(struct gsm_mux *
+ * will need moving to an ioctl path.
+ */
+
+-static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
++static void gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
+ {
+- unsigned int base;
+- int ret, i;
+-
+ gsm->tty = tty_kref_get(tty);
+ /* Turn off tty XON/XOFF handling to handle it explicitly. */
+ gsm->old_c_iflag = tty->termios.c_iflag;
+ tty->termios.c_iflag &= (IXON | IXOFF);
+- ret = gsm_activate_mux(gsm);
+- if (ret != 0)
+- tty_kref_put(gsm->tty);
+- else {
+- /* Don't register device 0 - this is the control channel and not
+- a usable tty interface */
+- base = mux_num_to_base(gsm); /* Base for this MUX */
+- for (i = 1; i < NUM_DLCI; i++) {
+- struct device *dev;
+-
+- dev = tty_register_device(gsm_tty_driver,
+- base + i, NULL);
+- if (IS_ERR(dev)) {
+- for (i--; i >= 1; i--)
+- tty_unregister_device(gsm_tty_driver,
+- base + i);
+- return PTR_ERR(dev);
+- }
+- }
+- }
+- return ret;
+ }
+
+-
+ /**
+ * gsmld_detach_gsm - stop doing 0710 mux
+ * @tty: tty attached to the mux
+@@ -2518,12 +2566,7 @@ static int gsmld_attach_gsm(struct tty_s
+
+ static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
+ {
+- unsigned int base = mux_num_to_base(gsm); /* Base for this MUX */
+- int i;
+-
+ WARN_ON(tty != gsm->tty);
+- for (i = 1; i < NUM_DLCI; i++)
+- tty_unregister_device(gsm_tty_driver, base + i);
+ /* Restore tty XON/XOFF handling. */
+ gsm->tty->termios.c_iflag = gsm->old_c_iflag;
+ tty_kref_put(gsm->tty);
+@@ -2619,7 +2662,6 @@ static void gsmld_close(struct tty_struc
+ static int gsmld_open(struct tty_struct *tty)
+ {
+ struct gsm_mux *gsm;
+- int ret;
+
+ if (tty->ops->write == NULL)
+ return -EINVAL;
+@@ -2635,12 +2677,11 @@ static int gsmld_open(struct tty_struct
+ /* Attach the initial passive connection */
+ gsm->encoding = 1;
+
+- ret = gsmld_attach_gsm(tty, gsm);
+- if (ret != 0) {
+- gsm_cleanup_mux(gsm, false);
+- mux_put(gsm);
+- }
+- return ret;
++ gsmld_attach_gsm(tty, gsm);
++
++ timer_setup(&gsm->t2_timer, gsm_control_retransmit, 0);
++
++ return 0;
+ }
+
+ /**
--- /dev/null
+From Ilia.Gavrilov@infotecs.ru Tue Dec 12 12:17:23 2023
+From: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
+Date: Tue, 12 Dec 2023 11:17:21 +0000
+Subject: tty: n_gsm, remove duplicates of parameters
+To: "stable@vger.kernel.org" <stable@vger.kernel.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Cc: Daniel Starke <daniel.starke@siemens.com>, Jiri Slaby <jirislaby@kernel.org>, Russ Gorby <russ.gorby@intel.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "lvc-project@linuxtesting.org" <lvc-project@linuxtesting.org>, Jiri Slaby <jslaby@suse.cz>
+Message-ID: <20231212111431.4064760-3-Ilia.Gavrilov@infotecs.ru>
+
+From: Jiri Slaby <jslaby@suse.cz>
+
+commit b93db97e1ca08e500305bc46b08c72e2232c4be1 upstream.
+
+dp, f, and i are only duplicates of gsmld_receive_buf's parameters. Use
+the parameters directly (cp, fp, and count) and delete these local
+variables.
+
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+Link: https://lore.kernel.org/r/20210302062214.29627-41-jslaby@suse.cz
+Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/n_gsm.c | 13 +++++--------
+ 1 file changed, 5 insertions(+), 8 deletions(-)
+
+--- a/drivers/tty/n_gsm.c
++++ b/drivers/tty/n_gsm.c
+@@ -2577,27 +2577,24 @@ static void gsmld_receive_buf(struct tty
+ char *fp, int count)
+ {
+ struct gsm_mux *gsm = tty->disc_data;
+- const unsigned char *dp;
+- char *f;
+- int i;
+ char flags = TTY_NORMAL;
+
+ if (debug & 4)
+ print_hex_dump_bytes("gsmld_receive: ", DUMP_PREFIX_OFFSET,
+ cp, count);
+
+- for (i = count, dp = cp, f = fp; i; i--, dp++) {
+- if (f)
+- flags = *f++;
++ for (; count; count--, cp++) {
++ if (fp)
++ flags = *fp++;
+ switch (flags) {
+ case TTY_NORMAL:
+- gsm->receive(gsm, *dp);
++ gsm->receive(gsm, *cp);
+ break;
+ case TTY_OVERRUN:
+ case TTY_BREAK:
+ case TTY_PARITY:
+ case TTY_FRAME:
+- gsm_error(gsm, *dp, flags);
++ gsm_error(gsm, *cp, flags);
+ break;
+ default:
+ WARN_ONCE(1, "%s: unknown flag %d\n",
projects / thirdparty / kernel / stable-queue.git / commitdiff
