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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /tools/objtool/signal.c
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'tools/objtool/signal.c')
-rw-r--r--tools/objtool/signal.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/tools/objtool/signal.c b/tools/objtool/signal.c
new file mode 100644
index 000000000..af5c65c0f
--- /dev/null
+++ b/tools/objtool/signal.c
@@ -0,0 +1,135 @@
+/*
+ * signal.c: Register a sigaltstack for objtool, to be able to
+ * run a signal handler on a separate stack even if
+ * the main process stack has overflown. Print out
+ * stack overflow errors when this happens.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/resource.h>
+#include <string.h>
+
+#include <objtool/objtool.h>
+#include <objtool/warn.h>
+
+static unsigned long stack_limit;
+
+static bool is_stack_overflow(void *fault_addr)
+{
+ unsigned long fault = (unsigned long)fault_addr;
+
+ /* Check if fault is in the guard page just below the limit. */
+ return fault < stack_limit && fault >= stack_limit - 4096;
+}
+
+static void signal_handler(int sig_num, siginfo_t *info, void *context)
+{
+ struct sigaction sa_dfl = {0};
+ const char *sig_name;
+ char msg[256];
+ int msg_len;
+
+ switch (sig_num) {
+ case SIGSEGV: sig_name = "SIGSEGV"; break;
+ case SIGBUS: sig_name = "SIGBUS"; break;
+ case SIGILL: sig_name = "SIGILL"; break;
+ case SIGABRT: sig_name = "SIGABRT"; break;
+ default: sig_name = "Unknown signal"; break;
+ }
+
+ if (is_stack_overflow(info->si_addr)) {
+ msg_len = snprintf(msg, sizeof(msg),
+ "%s: error: %s: objtool stack overflow!\n",
+ objname, sig_name);
+ } else {
+ msg_len = snprintf(msg, sizeof(msg),
+ "%s: error: %s: objtool crash!\n",
+ objname, sig_name);
+ }
+
+ msg_len = write(STDERR_FILENO, msg, msg_len);
+
+ /* Re-raise the signal to trigger the core dump */
+ sa_dfl.sa_handler = SIG_DFL;
+ sigaction(sig_num, &sa_dfl, NULL);
+ raise(sig_num);
+}
+
+static int read_stack_limit(void)
+{
+ unsigned long stack_start, stack_end;
+ struct rlimit rlim;
+ char line[256];
+ int ret = 0;
+ FILE *fp;
+
+ if (getrlimit(RLIMIT_STACK, &rlim)) {
+ ERROR_GLIBC("getrlimit");
+ return -1;
+ }
+
+ fp = fopen("/proc/self/maps", "r");
+ if (!fp) {
+ ERROR_GLIBC("fopen");
+ return -1;
+ }
+
+ while (fgets(line, sizeof(line), fp)) {
+ if (strstr(line, "[stack]")) {
+ if (sscanf(line, "%lx-%lx", &stack_start, &stack_end) != 2) {
+ ERROR_GLIBC("sscanf");
+ ret = -1;
+ goto done;
+ }
+ stack_limit = stack_end - rlim.rlim_cur;
+ goto done;
+ }
+ }
+
+ ret = -1;
+ ERROR("/proc/self/maps: can't find [stack]");
+
+done:
+ fclose(fp);
+
+ return ret;
+}
+
+int init_signal_handler(void)
+{
+ int signals[] = {SIGSEGV, SIGBUS, SIGILL, SIGABRT};
+ struct sigaction sa;
+ stack_t ss;
+
+ if (read_stack_limit())
+ return -1;
+
+ ss.ss_sp = malloc(SIGSTKSZ);
+ if (!ss.ss_sp) {
+ ERROR_GLIBC("malloc");
+ return -1;
+ }
+ ss.ss_size = SIGSTKSZ;
+ ss.ss_flags = 0;
+
+ if (sigaltstack(&ss, NULL) == -1) {
+ ERROR_GLIBC("sigaltstack");
+ return -1;
+ }
+
+ sa.sa_sigaction = signal_handler;
+ sigemptyset(&sa.sa_mask);
+
+ sa.sa_flags = SA_ONSTACK | SA_SIGINFO;
+
+ for (int i = 0; i < ARRAY_SIZE(signals); i++) {
+ if (sigaction(signals[i], &sa, NULL) == -1) {
+ ERROR_GLIBC("sigaction");
+ return -1;
+ }
+ }
+
+ return 0;
+}