From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
Alexander Sverdlin <alexander.sverdlin@nokia.com>,
Russell King <rmk+kernel@armlinux.org.uk>,
Florian Fainelli <f.fainelli@gmail.com>
Subject: [PATCH 4.9 51/57] ARM: 9079/1: ftrace: Add MODULE_PLTS support
Date: Mon, 4 Oct 2021 14:52:35 +0200 [thread overview]
Message-ID: <20211004125030.562670629@linuxfoundation.org> (raw)
In-Reply-To: <20211004125028.940212411@linuxfoundation.org>
From: Alex Sverdlin <alexander.sverdlin@nokia.com>
commit 79f32b221b18c15a98507b101ef4beb52444cc6f upstream
Teach ftrace_make_call() and ftrace_make_nop() about PLTs.
Teach PLT code about FTRACE and all its callbacks.
Otherwise the following might happen:
------------[ cut here ]------------
WARNING: CPU: 14 PID: 2265 at .../arch/arm/kernel/insn.c:14 __arm_gen_branch+0x83/0x8c()
...
Hardware name: LSI Axxia AXM55XX
[<c0314a49>] (unwind_backtrace) from [<c03115e9>] (show_stack+0x11/0x14)
[<c03115e9>] (show_stack) from [<c0519f51>] (dump_stack+0x81/0xa8)
[<c0519f51>] (dump_stack) from [<c032185d>] (warn_slowpath_common+0x69/0x90)
[<c032185d>] (warn_slowpath_common) from [<c03218f3>] (warn_slowpath_null+0x17/0x1c)
[<c03218f3>] (warn_slowpath_null) from [<c03143cf>] (__arm_gen_branch+0x83/0x8c)
[<c03143cf>] (__arm_gen_branch) from [<c0314337>] (ftrace_make_nop+0xf/0x24)
[<c0314337>] (ftrace_make_nop) from [<c038ebcb>] (ftrace_process_locs+0x27b/0x3e8)
[<c038ebcb>] (ftrace_process_locs) from [<c0378d79>] (load_module+0x11e9/0x1a44)
[<c0378d79>] (load_module) from [<c037974d>] (SyS_finit_module+0x59/0x84)
[<c037974d>] (SyS_finit_module) from [<c030e981>] (ret_fast_syscall+0x1/0x18)
---[ end trace e1b64ced7a89adcc ]---
------------[ cut here ]------------
WARNING: CPU: 14 PID: 2265 at .../kernel/trace/ftrace.c:1979 ftrace_bug+0x1b1/0x234()
...
Hardware name: LSI Axxia AXM55XX
[<c0314a49>] (unwind_backtrace) from [<c03115e9>] (show_stack+0x11/0x14)
[<c03115e9>] (show_stack) from [<c0519f51>] (dump_stack+0x81/0xa8)
[<c0519f51>] (dump_stack) from [<c032185d>] (warn_slowpath_common+0x69/0x90)
[<c032185d>] (warn_slowpath_common) from [<c03218f3>] (warn_slowpath_null+0x17/0x1c)
[<c03218f3>] (warn_slowpath_null) from [<c038e87d>] (ftrace_bug+0x1b1/0x234)
[<c038e87d>] (ftrace_bug) from [<c038ebd5>] (ftrace_process_locs+0x285/0x3e8)
[<c038ebd5>] (ftrace_process_locs) from [<c0378d79>] (load_module+0x11e9/0x1a44)
[<c0378d79>] (load_module) from [<c037974d>] (SyS_finit_module+0x59/0x84)
[<c037974d>] (SyS_finit_module) from [<c030e981>] (ret_fast_syscall+0x1/0x18)
---[ end trace e1b64ced7a89adcd ]---
ftrace failed to modify [<e9ef7006>] 0xe9ef7006
actual: 02:f0:3b:fa
ftrace record flags: 0
(0) expected tramp: c0314265
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm/include/asm/ftrace.h | 3 ++
arch/arm/include/asm/module.h | 1
arch/arm/kernel/ftrace.c | 45 +++++++++++++++++++++++++++++++++++-------
arch/arm/kernel/module-plts.c | 44 +++++++++++++++++++++++++++++++++++++----
4 files changed, 82 insertions(+), 11 deletions(-)
--- a/arch/arm/include/asm/ftrace.h
+++ b/arch/arm/include/asm/ftrace.h
@@ -14,6 +14,9 @@ struct dyn_arch_ftrace {
#ifdef CONFIG_OLD_MCOUNT
bool old_mcount;
#endif
+#ifdef CONFIG_ARM_MODULE_PLTS
+ struct module *mod;
+#endif
};
static inline unsigned long ftrace_call_adjust(unsigned long addr)
--- a/arch/arm/include/asm/module.h
+++ b/arch/arm/include/asm/module.h
@@ -29,6 +29,7 @@ struct plt_entries {
struct mod_plt_sec {
struct elf32_shdr *plt;
+ struct plt_entries *plt_ent;
int plt_count;
};
--- a/arch/arm/kernel/ftrace.c
+++ b/arch/arm/kernel/ftrace.c
@@ -95,9 +95,10 @@ int ftrace_arch_code_modify_post_process
return 0;
}
-static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
+static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr,
+ bool warn)
{
- return arm_gen_branch_link(pc, addr, true);
+ return arm_gen_branch_link(pc, addr, warn);
}
static int ftrace_modify_code(unsigned long pc, unsigned long old,
@@ -136,14 +137,14 @@ int ftrace_update_ftrace_func(ftrace_fun
int ret;
pc = (unsigned long)&ftrace_call;
- new = ftrace_call_replace(pc, (unsigned long)func);
+ new = ftrace_call_replace(pc, (unsigned long)func, true);
ret = ftrace_modify_code(pc, 0, new, false);
#ifdef CONFIG_OLD_MCOUNT
if (!ret) {
pc = (unsigned long)&ftrace_call_old;
- new = ftrace_call_replace(pc, (unsigned long)func);
+ new = ftrace_call_replace(pc, (unsigned long)func, true);
ret = ftrace_modify_code(pc, 0, new, false);
}
@@ -156,9 +157,21 @@ int ftrace_make_call(struct dyn_ftrace *
{
unsigned long new, old;
unsigned long ip = rec->ip;
+ unsigned long aaddr = adjust_address(rec, addr);
+ struct module *mod = NULL;
+
+#ifdef CONFIG_ARM_MODULE_PLTS
+ mod = rec->arch.mod;
+#endif
old = ftrace_nop_replace(rec);
- new = ftrace_call_replace(ip, adjust_address(rec, addr));
+ new = ftrace_call_replace(ip, aaddr, !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+ if (!new && mod) {
+ aaddr = get_module_plt(mod, ip, aaddr);
+ new = ftrace_call_replace(ip, aaddr, true);
+ }
+#endif
return ftrace_modify_code(rec->ip, old, new, true);
}
@@ -166,12 +179,29 @@ int ftrace_make_call(struct dyn_ftrace *
int ftrace_make_nop(struct module *mod,
struct dyn_ftrace *rec, unsigned long addr)
{
+ unsigned long aaddr = adjust_address(rec, addr);
unsigned long ip = rec->ip;
unsigned long old;
unsigned long new;
int ret;
- old = ftrace_call_replace(ip, adjust_address(rec, addr));
+#ifdef CONFIG_ARM_MODULE_PLTS
+ /* mod is only supplied during module loading */
+ if (!mod)
+ mod = rec->arch.mod;
+ else
+ rec->arch.mod = mod;
+#endif
+
+ old = ftrace_call_replace(ip, aaddr,
+ !IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+ if (!old && mod) {
+ aaddr = get_module_plt(mod, ip, aaddr);
+ old = ftrace_call_replace(ip, aaddr, true);
+ }
+#endif
+
new = ftrace_nop_replace(rec);
ret = ftrace_modify_code(ip, old, new, true);
@@ -179,7 +209,8 @@ int ftrace_make_nop(struct module *mod,
if (ret == -EINVAL && addr == MCOUNT_ADDR) {
rec->arch.old_mcount = true;
- old = ftrace_call_replace(ip, adjust_address(rec, addr));
+ old = ftrace_call_replace(ip, adjust_address(rec, addr),
+ !IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || !mod);
new = ftrace_nop_replace(rec);
ret = ftrace_modify_code(ip, old, new, true);
}
--- a/arch/arm/kernel/module-plts.c
+++ b/arch/arm/kernel/module-plts.c
@@ -7,6 +7,7 @@
*/
#include <linux/elf.h>
+#include <linux/ftrace.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sort.h>
@@ -22,19 +23,52 @@
(PLT_ENT_STRIDE - 8))
#endif
+static const u32 fixed_plts[] = {
+#ifdef CONFIG_FUNCTION_TRACER
+ FTRACE_ADDR,
+ MCOUNT_ADDR,
+#endif
+};
+
static bool in_init(const struct module *mod, unsigned long loc)
{
return loc - (u32)mod->init_layout.base < mod->init_layout.size;
}
+static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt)
+{
+ int i;
+
+ if (!ARRAY_SIZE(fixed_plts) || pltsec->plt_count)
+ return;
+ pltsec->plt_count = ARRAY_SIZE(fixed_plts);
+
+ for (i = 0; i < ARRAY_SIZE(plt->ldr); ++i)
+ plt->ldr[i] = PLT_ENT_LDR;
+
+ BUILD_BUG_ON(sizeof(fixed_plts) > sizeof(plt->lit));
+ memcpy(plt->lit, fixed_plts, sizeof(fixed_plts));
+}
+
u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val)
{
struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core :
&mod->arch.init;
+ struct plt_entries *plt;
+ int idx;
+
+ /* cache the address, ELF header is available only during module load */
+ if (!pltsec->plt_ent)
+ pltsec->plt_ent = (struct plt_entries *)pltsec->plt->sh_addr;
+ plt = pltsec->plt_ent;
- struct plt_entries *plt = (struct plt_entries *)pltsec->plt->sh_addr;
- int idx = 0;
+ prealloc_fixed(pltsec, plt);
+
+ for (idx = 0; idx < ARRAY_SIZE(fixed_plts); ++idx)
+ if (plt->lit[idx] == val)
+ return (u32)&plt->ldr[idx];
+ idx = 0;
/*
* Look for an existing entry pointing to 'val'. Given that the
* relocations are sorted, this will be the last entry we allocated.
@@ -182,8 +216,8 @@ static unsigned int count_plts(const Elf
int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
char *secstrings, struct module *mod)
{
- unsigned long core_plts = 0;
- unsigned long init_plts = 0;
+ unsigned long core_plts = ARRAY_SIZE(fixed_plts);
+ unsigned long init_plts = ARRAY_SIZE(fixed_plts);
Elf32_Shdr *s, *sechdrs_end = sechdrs + ehdr->e_shnum;
Elf32_Sym *syms = NULL;
@@ -238,6 +272,7 @@ int module_frob_arch_sections(Elf_Ehdr *
mod->arch.core.plt->sh_size = round_up(core_plts * PLT_ENT_SIZE,
sizeof(struct plt_entries));
mod->arch.core.plt_count = 0;
+ mod->arch.core.plt_ent = NULL;
mod->arch.init.plt->sh_type = SHT_NOBITS;
mod->arch.init.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
@@ -245,6 +280,7 @@ int module_frob_arch_sections(Elf_Ehdr *
mod->arch.init.plt->sh_size = round_up(init_plts * PLT_ENT_SIZE,
sizeof(struct plt_entries));
mod->arch.init.plt_count = 0;
+ mod->arch.init.plt_ent = NULL;
pr_debug("%s: plt=%x, init.plt=%x\n", __func__,
mod->arch.core.plt->sh_size, mod->arch.init.plt->sh_size);
next prev parent reply other threads:[~2021-10-04 13:00 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-04 12:51 [PATCH 4.9 00/57] 4.9.285-rc1 review Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 01/57] ocfs2: drop acl cache for directories too Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 02/57] usb: gadget: r8a66597: fix a loop in set_feature() Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 03/57] usb: musb: tusb6010: uninitialized data in tusb_fifo_write_unaligned() Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 04/57] cifs: fix incorrect check for null pointer in header_assemble Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 05/57] xen/x86: fix PV trap handling on secondary processors Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 06/57] usb-storage: Add quirk for ScanLogic SL11R-IDE older than 2.6c Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 07/57] USB: serial: cp210x: add ID for GW Instek GDM-834x Digital Multimeter Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 08/57] staging: greybus: uart: fix tty use after free Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 09/57] USB: serial: mos7840: remove duplicated 0xac24 device ID Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 10/57] USB: serial: option: add Telit LN920 compositions Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 11/57] USB: serial: option: remove duplicate USB device ID Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 12/57] USB: serial: option: add device id for Foxconn T99W265 Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 13/57] mcb: fix error handling in mcb_alloc_bus() Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 14/57] serial: mvebu-uart: fix drivers tx_empty callback Greg Kroah-Hartman
2021-10-04 12:51 ` [PATCH 4.9 15/57] net: hso: fix muxed tty registration Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 16/57] net/mlx4_en: Dont allow aRFS for encapsulated packets Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 17/57] scsi: iscsi: Adjust iface sysfs attr detection Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 18/57] blktrace: Fix uaf in blk_trace access after removing by sysfs Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 19/57] net: stmmac: allow CSR clock of 300MHz Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 20/57] m68k: Double cast io functions to unsigned long Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 21/57] compiler.h: Introduce absolute_pointer macro Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 22/57] net: i825xx: Use absolute_pointer for memcpy from fixed memory location Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 23/57] sparc: avoid stringop-overread errors Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 24/57] qnx4: " Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 25/57] parisc: Use absolute_pointer() to define PAGE0 Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 26/57] arm64: Mark __stack_chk_guard as __ro_after_init Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 27/57] alpha: Declare virt_to_phys and virt_to_bus parameter as pointer to volatile Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 28/57] net: 6pack: Fix tx timeout and slot time Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 29/57] spi: Fix tegra20 build with CONFIG_PM=n Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 30/57] arm64: dts: marvell: armada-37xx: Extend PCIe MEM space Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 31/57] qnx4: work around gcc false positive warning bug Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 32/57] tty: Fix out-of-bound vmalloc access in imageblit Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 33/57] cpufreq: schedutil: Use kobject release() method to free sugov_tunables Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 34/57] cpufreq: schedutil: Destroy mutex before kobject_put() frees the memory Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 35/57] mac80211: fix use-after-free in CCMP/GCMP RX Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 36/57] ipvs: check that ip_vs_conn_tab_bits is between 8 and 20 Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 37/57] mac80211: limit injected vht mcs/nss in ieee80211_parse_tx_radiotap Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 38/57] hwmon: (tmp421) fix rounding for negative values Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 39/57] e100: fix length calculation in e100_get_regs_len Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 40/57] e100: fix buffer overrun in e100_get_regs Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 41/57] ipack: ipoctal: fix stack information leak Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 42/57] ipack: ipoctal: fix tty registration race Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 43/57] ipack: ipoctal: fix tty-registration error handling Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 44/57] ipack: ipoctal: fix missing allocation-failure check Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 45/57] ipack: ipoctal: fix module reference leak Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 46/57] ext4: fix potential infinite loop in ext4_dx_readdir() Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 47/57] net: udp: annotate data race around udp_sk(sk)->corkflag Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 48/57] EDAC/synopsys: Fix wrong value type assignment for edac_mode Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 49/57] ARM: 9077/1: PLT: Move struct plt_entries definition to header Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 50/57] ARM: 9078/1: Add warn suppress parameter to arm_gen_branch_link() Greg Kroah-Hartman
2021-10-04 12:52 ` Greg Kroah-Hartman [this message]
2021-10-04 12:52 ` [PATCH 4.9 52/57] ARM: 9098/1: ftrace: MODULE_PLT: Fix build problem without DYNAMIC_FTRACE Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 53/57] arm64: Extend workaround for erratum 1024718 to all versions of Cortex-A55 Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 54/57] HID: betop: fix slab-out-of-bounds Write in betop_probe Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 55/57] netfilter: ipset: Fix oversized kvmalloc() calls Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 56/57] HID: usbhid: free raw_report buffers in usbhid_stop Greg Kroah-Hartman
2021-10-04 12:52 ` [PATCH 4.9 57/57] net: mdiobus: Fix memory leak in __mdiobus_register Greg Kroah-Hartman
2021-10-04 20:35 ` Florian Fainelli
2021-10-05 6:54 ` Greg Kroah-Hartman
2021-10-04 19:50 ` [PATCH 4.9 00/57] 4.9.285-rc1 review Shuah Khan
2021-10-05 2:13 ` Guenter Roeck
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20211004125030.562670629@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=alexander.sverdlin@nokia.com \
--cc=f.fainelli@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rmk+kernel@armlinux.org.uk \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox