1 files changed, 157 insertions, 164 deletions

diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c
index 8387a9bc064a..612268eabef4 100644
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -27,7 +27,6 @@
 #include <getopt.h>
 #include <elf.h>
 #include <fcntl.h>
-#include <setjmp.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -43,56 +42,37 @@ static int fd_map;	/* File descriptor for file being modified. */
 static int mmap_failed; /* Boolean flag. */
 static char gpfx;	/* prefix for global symbol name (sometimes '_') */
 static struct stat sb;	/* Remember .st_size, etc. */
-static jmp_buf jmpenv;	/* setjmp/longjmp per-file error escape */
 static const char *altmcount;	/* alternate mcount symbol name */
 static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */
 static void *file_map;	/* pointer of the mapped file */
 static void *file_end;	/* pointer to the end of the mapped file */
 static int file_updated; /* flag to state file was changed */
 static void *file_ptr;	/* current file pointer location */
+
 static void *file_append; /* added to the end of the file */
 static size_t file_append_size; /* how much is added to end of file */
 
-/* setjmp() return values */
-enum {
-	SJ_SETJMP = 0,  /* hardwired first return */
-	SJ_FAIL,
-	SJ_SUCCEED
-};
-
 /* Per-file resource cleanup when multiple files. */
-static void
-cleanup(void)
+static void file_append_cleanup(void)
 {
-	if (!mmap_failed)
-		munmap(file_map, sb.st_size);
-	else
-		free(file_map);
-	file_map = NULL;
 	free(file_append);
 	file_append = NULL;
 	file_append_size = 0;
 	file_updated = 0;
 }
 
-static void __attribute__((noreturn))
-fail_file(void)
+static void mmap_cleanup(void)
 {
-	cleanup();
-	longjmp(jmpenv, SJ_FAIL);
-}
-
-static void __attribute__((noreturn))
-succeed_file(void)
-{
-	cleanup();
-	longjmp(jmpenv, SJ_SUCCEED);
+	if (!mmap_failed)
+		munmap(file_map, sb.st_size);
+	else
+		free(file_map);
+	file_map = NULL;
 }
 
-/* ulseek, uread, ...:  Check return value for errors. */
+/* ulseek, uwrite, ...:  Check return value for errors. */
 
-static off_t
-ulseek(int const fd, off_t const offset, int const whence)
+static off_t ulseek(off_t const offset, int const whence)
 {
 	switch (whence) {
 	case SEEK_SET:
@@ -107,24 +87,12 @@ ulseek(int const fd, off_t const offset, int const whence)
 	}
 	if (file_ptr < file_map) {
 		fprintf(stderr, "lseek: seek before file\n");
-		fail_file();
+		return -1;
 	}
 	return file_ptr - file_map;
 }
 
-static size_t
-uread(int const fd, void *const buf, size_t const count)
-{
-	size_t const n = read(fd, buf, count);
-	if (n != count) {
-		perror("read");
-		fail_file();
-	}
-	return n;
-}
-
-static size_t
-uwrite(int const fd, void const *const buf, size_t const count)
+static ssize_t uwrite(void const *const buf, size_t const count)
 {
 	size_t cnt = count;
 	off_t idx = 0;
@@ -140,7 +108,9 @@ uwrite(int const fd, void const *const buf, size_t const count)
 		}
 		if (!file_append) {
 			perror("write");
-			fail_file();
+			file_append_cleanup();
+			mmap_cleanup();
+			return -1;
 		}
 		if (file_ptr < file_end) {
 			cnt = file_end - file_ptr;
@@ -160,17 +130,81 @@ uwrite(int const fd, void const *const buf, size_t const count)
 	return count;
 }
 
-static void *
-umalloc(size_t size)
+static void * umalloc(size_t size)
 {
 	void *const addr = malloc(size);
 	if (addr == 0) {
 		fprintf(stderr, "malloc failed: %zu bytes\n", size);
-		fail_file();
+		file_append_cleanup();
+		mmap_cleanup();
+		return NULL;
 	}
 	return addr;
 }
 
+/*
+ * Get the whole file as a programming convenience in order to avoid
+ * malloc+lseek+read+free of many pieces.  If successful, then mmap
+ * avoids copying unused pieces; else just read the whole file.
+ * Open for both read and write; new info will be appended to the file.
+ * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr
+ * do not propagate to the file until an explicit overwrite at the last.
+ * This preserves most aspects of consistency (all except .st_size)
+ * for simultaneous readers of the file while we are appending to it.
+ * However, multiple writers still are bad.  We choose not to use
+ * locking because it is expensive and the use case of kernel build
+ * makes multiple writers unlikely.
+ */
+static void *mmap_file(char const *fname)
+{
+	/* Avoid problems if early cleanup() */
+	fd_map = -1;
+	mmap_failed = 1;
+	file_map = NULL;
+	file_ptr = NULL;
+	file_updated = 0;
+	sb.st_size = 0;
+
+	fd_map = open(fname, O_RDONLY);
+	if (fd_map < 0) {
+		perror(fname);
+		return NULL;
+	}
+	if (fstat(fd_map, &sb) < 0) {
+		perror(fname);
+		goto out;
+	}
+	if (!S_ISREG(sb.st_mode)) {
+		fprintf(stderr, "not a regular file: %s\n", fname);
+		goto out;
+	}
+	file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE,
+			fd_map, 0);
+	if (file_map == MAP_FAILED) {
+		mmap_failed = 1;
+		file_map = umalloc(sb.st_size);
+		if (!file_map) {
+			perror(fname);
+			goto out;
+		}
+		if (read(fd_map, file_map, sb.st_size) != sb.st_size) {
+			perror(fname);
+			free(file_map);
+			file_map = NULL;
+			goto out;
+		}
+	} else
+		mmap_failed = 0;
+out:
+	close(fd_map);
+	fd_map = -1;
+
+	file_end = file_map + sb.st_size;
+
+	return file_map;
+}
+
+
 static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };
 static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 };
 static unsigned char *ideal_nop;
@@ -194,8 +228,10 @@ static int make_nop_x86(void *map, size_t const offset)
 		return -1;
 
 	/* convert to nop */
-	ulseek(fd_map, offset - 1, SEEK_SET);
-	uwrite(fd_map, ideal_nop, 5);
+	if (ulseek(offset - 1, SEEK_SET) < 0)
+		return -1;
+	if (uwrite(ideal_nop, 5) < 0)
+		return -1;
 	return 0;
 }
 
@@ -243,10 +279,12 @@ static int make_nop_arm(void *map, size_t const offset)
 		return -1;
 
 	/* Convert to nop */
-	ulseek(fd_map, off, SEEK_SET);
+	if (ulseek(off, SEEK_SET) < 0)
+		return -1;
 
 	do {
-		uwrite(fd_map, ideal_nop, nop_size);
+		if (uwrite(ideal_nop, nop_size) < 0)
+			return -1;
 	} while (--cnt > 0);
 
 	return 0;
@@ -263,57 +301,20 @@ static int make_nop_arm64(void *map, size_t const offset)
 		return -1;
 
 	/* Convert to nop */
-	ulseek(fd_map, offset, SEEK_SET);
-	uwrite(fd_map, ideal_nop, 4);
+	if (ulseek(offset, SEEK_SET) < 0)
+		return -1;
+	if (uwrite(ideal_nop, 4) < 0)
+		return -1;
 	return 0;
 }
 
-/*
- * Get the whole file as a programming convenience in order to avoid
- * malloc+lseek+read+free of many pieces.  If successful, then mmap
- * avoids copying unused pieces; else just read the whole file.
- * Open for both read and write; new info will be appended to the file.
- * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr
- * do not propagate to the file until an explicit overwrite at the last.
- * This preserves most aspects of consistency (all except .st_size)
- * for simultaneous readers of the file while we are appending to it.
- * However, multiple writers still are bad.  We choose not to use
- * locking because it is expensive and the use case of kernel build
- * makes multiple writers unlikely.
- */
-static void *mmap_file(char const *fname)
-{
-	fd_map = open(fname, O_RDONLY);
-	if (fd_map < 0 || fstat(fd_map, &sb) < 0) {
-		perror(fname);
-		fail_file();
-	}
-	if (!S_ISREG(sb.st_mode)) {
-		fprintf(stderr, "not a regular file: %s\n", fname);
-		fail_file();
-	}
-	file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE,
-			fd_map, 0);
-	mmap_failed = 0;
-	if (file_map == MAP_FAILED) {
-		mmap_failed = 1;
-		file_map = umalloc(sb.st_size);
-		uread(fd_map, file_map, sb.st_size);
-	}
-	close(fd_map);
-
-	file_end = file_map + sb.st_size;
-
-	return file_map;
-}
-
-static void write_file(const char *fname)
+static int write_file(const char *fname)
 {
 	char tmp_file[strlen(fname) + 4];
 	size_t n;
 
 	if (!file_updated)
-		return;
+		return 0;
 
 	sprintf(tmp_file, "%s.rc", fname);
 
@@ -325,25 +326,28 @@ static void write_file(const char *fname)
 	fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode);
 	if (fd_map < 0) {
 		perror(fname);
-		fail_file();
+		return -1;
 	}
 	n = write(fd_map, file_map, sb.st_size);
 	if (n != sb.st_size) {
 		perror("write");
-		fail_file();
+		close(fd_map);
+		return -1;
 	}
 	if (file_append_size) {
 		n = write(fd_map, file_append, file_append_size);
 		if (n != file_append_size) {
 			perror("write");
-			fail_file();
+			close(fd_map);
+			return -1;
 		}
 	}
 	close(fd_map);
 	if (rename(tmp_file, fname) < 0) {
 		perror(fname);
-		fail_file();
+		return -1;
 	}
+	return 0;
 }
 
 /* w8rev, w8nat, ...: Handle endianness. */
@@ -394,8 +398,7 @@ static uint32_t (*w)(uint32_t);
 static uint32_t (*w2)(uint16_t);
 
 /* Names of the sections that could contain calls to mcount. */
-static int
-is_mcounted_section_name(char const *const txtname)
+static int is_mcounted_section_name(char const *const txtname)
 {
 	return strncmp(".text",          txtname, 5) == 0 ||
 		strcmp(".init.text",     txtname) == 0 ||
@@ -405,10 +408,11 @@ is_mcounted_section_name(char const *const txtname)
 		strcmp(".irqentry.text", txtname) == 0 ||
 		strcmp(".softirqentry.text", txtname) == 0 ||
 		strcmp(".kprobes.text", txtname) == 0 ||
-		strcmp(".cpuidle.text", txtname) == 0 ||
-		strcmp(".text.unlikely", txtname) == 0;
+		strcmp(".cpuidle.text", txtname) == 0;
 }
 
+static char const *already_has_rel_mcount = "success"; /* our work here is done! */
+
 /* 32 bit and 64 bit are very similar */
 #include "recordmcount.h"
 #define RECORD_MCOUNT_64
@@ -447,11 +451,15 @@ static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type)
 	}).r_info;
 }
 
-static void
-do_file(char const *const fname)
+static int do_file(char const *const fname)
 {
-	Elf32_Ehdr *const ehdr = mmap_file(fname);
 	unsigned int reltype = 0;
+	Elf32_Ehdr *ehdr;
+	int rc = -1;
+
+	ehdr = mmap_file(fname);
+	if (!ehdr)
+		goto out;
 
 	w = w4nat;
 	w2 = w2nat;
@@ -461,8 +469,7 @@ do_file(char const *const fname)
 	default:
 		fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
 			ehdr->e_ident[EI_DATA], fname);
-		fail_file();
-		break;
+		goto out;
 	case ELFDATA2LSB:
 		if (*(unsigned char const *)&endian != 1) {
 			/* main() is big endian, file.o is little endian. */
@@ -490,52 +497,54 @@ do_file(char const *const fname)
 		push_bl_mcount_thumb = push_bl_mcount_thumb_be;
 		break;
 	}  /* end switch */
-	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
-	||  w2(ehdr->e_type) != ET_REL
-	||  ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
+	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 ||
+	    w2(ehdr->e_type) != ET_REL ||
+	    ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
 		fprintf(stderr, "unrecognized ET_REL file %s\n", fname);
-		fail_file();
+		goto out;
 	}
 
-	gpfx = 0;
+	gpfx = '_';
 	switch (w2(ehdr->e_machine)) {
 	default:
 		fprintf(stderr, "unrecognized e_machine %u %s\n",
 			w2(ehdr->e_machine), fname);
-		fail_file();
-		break;
+		goto out;
 	case EM_386:
 		reltype = R_386_32;
 		rel_type_nop = R_386_NONE;
 		make_nop = make_nop_x86;
 		ideal_nop = ideal_nop5_x86_32;
 		mcount_adjust_32 = -1;
+		gpfx = 0;
+		break;
+	case EM_ARM:
+		reltype = R_ARM_ABS32;
+		altmcount = "__gnu_mcount_nc";
+		make_nop = make_nop_arm;
+		rel_type_nop = R_ARM_NONE;
+		gpfx = 0;
 		break;
-	case EM_ARM:	 reltype = R_ARM_ABS32;
-			 altmcount = "__gnu_mcount_nc";
-			 make_nop = make_nop_arm;
-			 rel_type_nop = R_ARM_NONE;
-			 break;
 	case EM_AARCH64:
-			reltype = R_AARCH64_ABS64;
-			make_nop = make_nop_arm64;
-			rel_type_nop = R_AARCH64_NONE;
-			ideal_nop = ideal_nop4_arm64;
-			gpfx = '_';
-			break;
-	case EM_IA_64:	 reltype = R_IA64_IMM64;   gpfx = '_'; break;
-	case EM_MIPS:	 /* reltype: e_class    */ gpfx = '_'; break;
-	case EM_PPC:	 reltype = R_PPC_ADDR32;   gpfx = '_'; break;
-	case EM_PPC64:	 reltype = R_PPC64_ADDR64; gpfx = '_'; break;
-	case EM_S390:    /* reltype: e_class    */ gpfx = '_'; break;
-	case EM_SH:	 reltype = R_SH_DIR32;                 break;
-	case EM_SPARCV9: reltype = R_SPARC_64;     gpfx = '_'; break;
+		reltype = R_AARCH64_ABS64;
+		make_nop = make_nop_arm64;
+		rel_type_nop = R_AARCH64_NONE;
+		ideal_nop = ideal_nop4_arm64;
+		break;
+	case EM_IA_64:	reltype = R_IA64_IMM64; break;
+	case EM_MIPS:	/* reltype: e_class    */ break;
+	case EM_PPC:	reltype = R_PPC_ADDR32; break;
+	case EM_PPC64:	reltype = R_PPC64_ADDR64; break;
+	case EM_S390:	/* reltype: e_class    */ break;
+	case EM_SH:	reltype = R_SH_DIR32; gpfx = 0; break;
+	case EM_SPARCV9: reltype = R_SPARC_64; break;
 	case EM_X86_64:
 		make_nop = make_nop_x86;
 		ideal_nop = ideal_nop5_x86_64;
 		reltype = R_X86_64_64;
 		rel_type_nop = R_X86_64_NONE;
 		mcount_adjust_64 = -1;
+		gpfx = 0;
 		break;
 	}  /* end switch */
 
@@ -543,20 +552,20 @@ do_file(char const *const fname)
 	default:
 		fprintf(stderr, "unrecognized ELF class %d %s\n",
 			ehdr->e_ident[EI_CLASS], fname);
-		fail_file();
-		break;
+		goto out;
 	case ELFCLASS32:
 		if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
 		||  w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
 			fprintf(stderr,
 				"unrecognized ET_REL file: %s\n", fname);
-			fail_file();
+			goto out;
 		}
 		if (w2(ehdr->e_machine) == EM_MIPS) {
 			reltype = R_MIPS_32;
 			is_fake_mcount32 = MIPS32_is_fake_mcount;
 		}
-		do32(ehdr, fname, reltype);
+		if (do32(ehdr, fname, reltype) < 0)
+			goto out;
 		break;
 	case ELFCLASS64: {
 		Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
@@ -564,7 +573,7 @@ do_file(char const *const fname)
 		||  w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
 			fprintf(stderr,
 				"unrecognized ET_REL file: %s\n", fname);
-			fail_file();
+			goto out;
 		}
 		if (w2(ghdr->e_machine) == EM_S390) {
 			reltype = R_390_64;
@@ -576,17 +585,20 @@ do_file(char const *const fname)
 			Elf64_r_info = MIPS64_r_info;
 			is_fake_mcount64 = MIPS64_is_fake_mcount;
 		}
-		do64(ghdr, fname, reltype);
+		if (do64(ghdr, fname, reltype) < 0)
+			goto out;
 		break;
 	}
 	}  /* end switch */
 
-	write_file(fname);
-	cleanup();
+	rc = write_file(fname);
+out:
+	file_append_cleanup();
+	mmap_cleanup();
+	return rc;
 }
 
-int
-main(int argc, char *argv[])
+int main(int argc, char *argv[])
 {
 	const char ftrace[] = "/ftrace.o";
 	int ftrace_size = sizeof(ftrace) - 1;
@@ -613,7 +625,6 @@ main(int argc, char *argv[])
 	/* Process each file in turn, allowing deep failure. */
 	for (i = optind; i < argc; i++) {
 		char *file = argv[i];
-		int const sjval = setjmp(jmpenv);
 		int len;
 
 		/*
@@ -626,28 +637,10 @@ main(int argc, char *argv[])
 		    strcmp(file + (len - ftrace_size), ftrace) == 0)
 			continue;
 
-		switch (sjval) {
-		default:
-			fprintf(stderr, "internal error: %s\n", file);
-			exit(1);
-			break;
-		case SJ_SETJMP:    /* normal sequence */
-			/* Avoid problems if early cleanup() */
-			fd_map = -1;
-			mmap_failed = 1;
-			file_map = NULL;
-			file_ptr = NULL;
-			file_updated = 0;
-			do_file(file);
-			break;
-		case SJ_FAIL:    /* error in do_file or below */
+		if (do_file(file)) {
 			fprintf(stderr, "%s: failed\n", file);
 			++n_error;
-			break;
-		case SJ_SUCCEED:    /* premature success */
-			/* do nothing */
-			break;
-		}  /* end switch */
+		}
 	}
 	return !!n_error;
 }