Support resizing the BSS section with rabin2 -O ##bin

libr/bin/bin_write.c

@@ -1,64 +1,62 @@
-/* radare2 - LGPL - Copyright 2009-2019 - pancake, nibble */
+/* radare2 - LGPL - Copyright 2009-2024 - pancake, nibble */
 
-#include <r_types.h>
-#include <r_util.h>
 #include <r_bin.h>
 
 /* XXX Implement r__bin_wr_scn_{   set, del   } instead */
 // R2_600 evaluate return bool here
 R_API ut64 r_bin_wr_scn_resize(RBin *bin, const char *name, ut64 size) {
-	R_RETURN_VAL_IF_FAIL (bin, UT64_MAX);
+	R_RETURN_VAL_IF_FAIL (bin && name, UT64_MAX);
 	RBinFile *bf = r_bin_cur (bin);
 	RBinPlugin *plugin = r_bin_file_cur_plugin (bf);
-	if (plugin && plugin->write && plugin->write->scn_resize) {
-		return plugin->write->scn_resize (bf, name, size);
+	RBinWriteScnResize scn_resize = R_UNWRAP3 (plugin, write, scn_resize);
+	if (scn_resize) {
+		return scn_resize (bf, name, size);
 	}
 	return 0;
 }
 
 R_API bool r_bin_wr_scn_perms(RBin *bin, const char *name, int perms) {
+	R_RETURN_VAL_IF_FAIL (bin && name, false);
 	RBinFile *bf = r_bin_cur (bin);
 	RBinPlugin *plugin = r_bin_file_cur_plugin (bf);
-	if (plugin && plugin->write && plugin->write->scn_perms) {
-		return plugin->write->scn_perms (bf, name, perms);
+	RBinWriteScnPerms scn_perms = R_UNWRAP3 (plugin, write, scn_perms);
+	if (scn_perms) {
+		return scn_perms (bf, name, perms);
 	}
 	return false;
 }
 
 R_API bool r_bin_wr_rpath_del(RBin *bin) {
+	R_RETURN_VAL_IF_FAIL (bin, false);
 	RBinFile *bf = r_bin_cur (bin);
 	RBinPlugin *plugin = r_bin_file_cur_plugin (bf);
-	if (plugin && plugin->write && plugin->write->rpath_del) {
-		return plugin->write->rpath_del (bf);
-	}
-	return false;
+	RBinWriteRpathDel rpath_del = R_UNWRAP3 (plugin, write, rpath_del);
+	return rpath_del? rpath_del (bf): false;
 }
 
 R_API bool r_bin_wr_output(RBin *bin, const char *filename) {
-	r_return_val_if_fail (bin && filename, false);
+	R_RETURN_VAL_IF_FAIL (bin && filename, false);
 	RBinFile *bf = r_bin_cur (bin);
 	if (!bf || !bf->buf) {
 		return false;
 	}
-	ut64 tmpsz;
+	ut64 tmpsz = 0;
 	const ut8 *tmp = r_buf_data (bf->buf, &tmpsz);
 	return r_file_dump (filename, tmp, tmpsz, 0);
 }
 
 R_API bool r_bin_wr_entry(RBin *bin, ut64 addr) {
+	R_RETURN_VAL_IF_FAIL (bin, false);
 	RBinFile *bf = r_bin_cur (bin);
 	RBinPlugin *plugin = r_bin_file_cur_plugin (bf);
-	if (plugin && plugin->write && plugin->write->entry) {
-		return plugin->write->entry (bf, addr);
-	}
-	return false;
+	RBinWriteEntry entry = R_UNWRAP3 (plugin, write, entry);
+	return entry? entry (bf, addr): false;
 }
 
 R_API bool r_bin_wr_addlib(RBin *bin, const char *lib) {
+	R_RETURN_VAL_IF_FAIL (bin && lib, false);
 	RBinFile *bf = r_bin_cur (bin);
 	RBinPlugin *plugin = r_bin_file_cur_plugin (bf);
-	if (plugin && plugin->write && plugin->write->addlib) {
-		return plugin->write->addlib (bin->cur, lib);
-	}
-	return false;
+	RBinWriteAddLib addlib = R_UNWRAP3 (plugin, write, addlib);
+	return addlib? addlib (bin->cur, lib): false;
 }

libr/bin/format/elf/elf_write.c

@@ -1,4 +1,4 @@
-/* radare - LGPL - Copyright 2010-2023 pancake, nibble */
+/* radare - LGPL - Copyright 2010-2024 pancake, nibble */
 
 #include <r_util.h>
 #include "elf.h"
@@ -13,15 +13,15 @@ ut64 Elf_(resize_section)(RBinFile *bf, const char *name, ut64 size) {
 	Elf_(Phdr) *phdr = bin->phdr, *phdrp;
 	Elf_(Shdr) *shdr = bin->shdr, *shdrp;
 	const char *strtab = bin->shstrtab;
-	ut8 *buf;
 	ut64 off, got_offset = 0, got_addr = 0, rsz_offset = 0, delta = 0;
 	ut64 rsz_osize = 0, rsz_size = size, rest_size = 0;
 	int i, j, done = 0;
 
 	if (size == 0) {
-		eprintf ("0 size section?\n");
+		R_LOG_ERROR ("0 size section?");
 		return 0;
 	}
+	bool section_not_found = true;
 
 	/* calculate delta */
 	for (i = 0, shdrp = shdr; i < ehdr->e_shnum; i++, shdrp++) {
@@ -31,22 +31,33 @@ ut64 Elf_(resize_section)(RBinFile *bf, const char *name, ut64 size) {
 		}
 		const char *sh_name = &strtab[shdrp->sh_name];
 		if (sh_name && !strncmp (name, sh_name, ELF_STRING_LENGTH)) {
-			delta =  rsz_size - shdrp->sh_size;
-			rsz_offset = (ut64)shdrp->sh_offset;
-			rsz_osize = (ut64)shdrp->sh_size;
+			section_not_found = false;
+			if (shdrp->sh_type == 8) {
+				// is virtual section. so we only need to patch the headers
+				delta = 0;
+				shdrp->sh_size = rsz_size;
+				off = ehdr->e_shoff + (i * sizeof (Elf_(Shdr)));
+				r_buf_write_at (bf->buf, off, (ut8*)shdrp, sizeof (Elf_(Shdr)));
+				return 0;
+			} else {
+				delta = rsz_size - shdrp->sh_size;
+				rsz_offset = (ut64)shdrp->sh_offset;
+				rsz_osize = (ut64)shdrp->sh_size;
+			}
+			break;
 		}
 	}
 
-	if (delta == 0) {
+	if (section_not_found) {
 		R_LOG_ERROR ("Cannot find section");
 		return 0;
 	}
 
-	eprintf ("delta: %"PFMT64d"\n", delta);
+	R_LOG_INFO ("File size delta: %"PFMT64d, delta);
 
 	/* rewrite rel's (imports) */
 	for (i = 0, shdrp = shdr; i < ehdr->e_shnum; i++, shdrp++) {
-		if (!strcmp (&strtab[shdrp->sh_name], ".got")) {
+		if (!strncmp (&strtab[shdrp->sh_name], ".got", ELF_STRING_LENGTH)) {
 			got_addr = (ut64)shdrp->sh_addr;
 			got_offset = (ut64)shdrp->sh_offset;
 		}
@@ -56,20 +67,20 @@ ut64 Elf_(resize_section)(RBinFile *bf, const char *name, ut64 size) {
 	}
 
 	for (i = 0, shdrp = shdr; i < ehdr->e_shnum; i++, shdrp++) {
-		if (!strcmp (&strtab[shdrp->sh_name], ".rel.plt")) {
+		if (!strncmp (&strtab[shdrp->sh_name], ".rel.plt", ELF_STRING_LENGTH)) {
 			Elf_(Rel) *rel, *relp;
 			rel = (Elf_(Rel) *)malloc (1 + shdrp->sh_size);
 			if (!rel) {
 				r_sys_perror ("malloc");
 				return 0;
 			}
 			if (r_buf_read_at (bin->b, shdrp->sh_offset, (ut8*)rel, shdrp->sh_size) == -1) {
-				r_sys_perror("read (rel)");
+				r_sys_perror ("read (rel)");
 			}
 			for (j = 0, relp = rel; j < shdrp->sh_size; j += sizeof (Elf_(Rel)), relp++) {
 				/* rewrite relp->r_offset */
 				if (relp->r_offset - got_addr + got_offset >= rsz_offset + rsz_osize) {
-					relp->r_offset+=delta;
+					relp->r_offset += delta;
 					off = shdrp->sh_offset + j;
 					if (r_buf_write_at (bin->b, off, (ut8*)relp, sizeof (Elf_(Rel))) == -1) {
 						r_sys_perror("write (imports)");
@@ -91,8 +102,8 @@ ut64 Elf_(resize_section)(RBinFile *bf, const char *name, ut64 size) {
 			for (j = 0, relp = rel; j < shdrp->sh_size; j += sizeof (Elf_(Rela)), relp++) {
 				/* rewrite relp->r_offset */
 				if (relp->r_offset - got_addr + got_offset >= rsz_offset + rsz_osize) {
-					relp->r_offset+=delta;
 					off = shdrp->sh_offset + j;
+					relp->r_offset += delta;
 					if (r_buf_write_at (bin->b, off, (ut8*)relp, sizeof (Elf_(Rela))) == -1) {
 						r_sys_perror("write (imports)");
 					}
@@ -105,20 +116,28 @@ ut64 Elf_(resize_section)(RBinFile *bf, const char *name, ut64 size) {
 
 	/* rewrite section headers */
 	for (i = 0, shdrp = shdr; i < ehdr->e_shnum; i++, shdrp++) {
-		if (!done && !strncmp (name, &strtab[shdrp->sh_name], ELF_STRING_LENGTH)) {
+		off = ehdr->e_shoff + (i * sizeof (Elf_(Shdr)));
+		if (!done && !strncmp (name, strtab + shdrp->sh_name, ELF_STRING_LENGTH)) {
+			R_LOG_INFO ("patching the virtual section size from %d to %d", shdrp->sh_size, rsz_size);
 			shdrp->sh_size = rsz_size;
-			done = 1;
+			r_buf_write_at (bf->buf, off + i, (ut8*)&shdrp, sizeof (Elf_(Shdr)));
+			done = true;
 		} else if (shdrp->sh_offset >= rsz_offset + rsz_osize) {
 			shdrp->sh_offset += delta;
 			if (shdrp->sh_addr) {
 				shdrp->sh_addr += delta;
 			}
 		}
-		off = ehdr->e_shoff + i * sizeof (Elf_(Shdr));
+		R_LOG_INFO ("patching write");
+#if 0
+		r_buf_write_at (bf->buf, off, (ut8*)&shdrp, sizeof (Elf_(Shdr)));
+#else
+		// TODO: write to bf->buf if the final bin needs to be patched
 		if (r_buf_write_at (bin->b, off, (ut8*)shdrp, sizeof (Elf_(Shdr))) == -1) {
 			r_sys_perror ("write (shdr)");
 		}
-		printf ("-> elf section (%s)\n", &strtab[shdrp->sh_name]);
+#endif
+		R_LOG_DEBUG ("-> elf section (%s)", strtab + shdrp->sh_name);
 	}
 
 	/* rewrite program headers */
@@ -151,36 +170,43 @@ ut64 Elf_(resize_section)(RBinFile *bf, const char *name, ut64 size) {
 	/* rewrite other elf pointers (entrypoint, phoff, shoff) */
 	if (ehdr->e_entry - bin->baddr >= rsz_offset + rsz_osize) {
 		ehdr->e_entry += delta;
+		R_LOG_INFO ("patch entry");
 	}
 	if (ehdr->e_phoff >= rsz_offset + rsz_osize) {
 		ehdr->e_phoff += delta;
+		R_LOG_INFO ("patch phoff");
 	}
 	if (ehdr->e_shoff >= rsz_offset + rsz_osize) {
 		ehdr->e_shoff += delta;
+		R_LOG_INFO ("patch shoff");
 	}
+	R_LOG_INFO ("writing ehdr");
 	if (r_buf_write_at (bin->b, 0, (ut8*)ehdr, sizeof (Elf_(Ehdr))) == -1) {
 		r_sys_perror ("write (ehdr)");
 	}
 
-	/* inverse order to write bodies .. avoid overlapping here */
+	/* Inverse order to write bodies to avoid overlapping */
 	/* XXX Check when delta is negative */
 	rest_size = bin->size - (rsz_offset + rsz_osize);
 
-	buf = (ut8 *)malloc (1 + bin->size);
-	if (!buf) {
-		R_LOG_ERROR ("Cannot allocate %d", bin->size);
-		return 0;
+	if (delta == 0) {
+		R_LOG_INFO ("Size unchanged");
+	} else {
+		ut8 *buf = (ut8 *)malloc (1 + bin->size);
+		if (!buf) {
+			R_LOG_ERROR ("Cannot allocate %d", bin->size);
+			return 0;
+		}
+		r_buf_read_at (bin->b, 0, (ut8*)buf, bin->size);
+		r_buf_set_bytes (bin->b, (ut8*)buf, (int)(rsz_offset + rsz_size + rest_size));
+		printf ("COPY FROM 0x%08"PFMT64x"\n", (ut64)(rsz_offset + rsz_osize));
+		r_buf_read_at (bin->b, rsz_offset + rsz_osize, (ut8*)buf, rest_size);
+		printf ("COPY TO 0x%08"PFMT64x"\n", (ut64)(rsz_offset + rsz_size));
+		r_buf_write_at (bin->b, rsz_offset + rsz_size, (ut8*)buf, rest_size);
+		printf ("Shifted %d byte(s)\n", (int)delta);
+		bin->size = r_buf_size (bin->b);
+		free (buf);
 	}
-	r_buf_read_at (bin->b, 0, (ut8*)buf, bin->size);
-	r_buf_set_bytes (bin->b, (ut8*)buf, (int)(rsz_offset + rsz_size + rest_size));
-
-	printf ("COPY FROM 0x%08"PFMT64x"\n", (ut64)(rsz_offset + rsz_osize));
-	r_buf_read_at (bin->b, rsz_offset + rsz_osize, (ut8*)buf, rest_size);
-	printf ("COPY TO 0x%08"PFMT64x"\n", (ut64)(rsz_offset+rsz_size));
-	r_buf_write_at (bin->b, rsz_offset + rsz_size, (ut8*)buf, rest_size);
-	printf ("Shifted %d byte(s)\n", (int)delta);
-	free (buf);
-	bin->size = r_buf_size (bin->b);
 
 	return delta;
 }

libr/core/cmd_anal.inc.c

@@ -13488,13 +13488,13 @@ static int cmd_anal_all(RCore *core, const char *input) {
 			r_core_cmd0 (core, "aef@@F");
 		} else if (input[1] == 'r') {
 			ut64 cur = core->offset;
-			bool hasnext = r_config_get_b (core->config, "anal.hasnext");
 			RListIter *iter;
 			RIOMap *map;
 			RList *list = r_core_get_boundaries_prot (core, R_PERM_X, NULL, "anal");
 			if (!list) {
 				break;
 			}
+			bool hasnext = r_config_get_b (core->config, "anal.hasnext");
 			r_list_foreach (list, iter, map) {
 				r_core_seek (core, r_io_map_begin (map), true);
 				r_config_set_b (core->config, "anal.hasnext", true);

libr/include/r_bin.h

@@ -700,12 +700,17 @@ typedef struct r_bin_dbginfo_t {
 	bool (*get_line)(RBinFile *arch, ut64 addr, char *file, int len, int *line, int *column);
 } RBinDbgInfo;
 
+typedef bool (*RBinWriteAddLib)(RBinFile *bf, const char *lib);
+typedef ut64 (*RBinWriteScnResize)(RBinFile *bf, const char *name, ut64 newsize);
+typedef bool (*RBinWriteScnPerms)(RBinFile *bf, const char *name, int perms);
+typedef bool (*RBinWriteEntry)(RBinFile *bf, ut64 addr);
+typedef int (*RBinWriteRpathDel)(RBinFile *bf);
 typedef struct r_bin_write_t {
-	ut64 (*scn_resize)(RBinFile *bf, const char *name, ut64 size); // R2_600 return bool instead
-	bool (*scn_perms)(RBinFile *bf, const char *name, int perms);
-	int (*rpath_del)(RBinFile *bf); // R2_600 return bool instead
-	bool (*entry)(RBinFile *bf, ut64 addr);
-	bool (*addlib)(RBinFile *bf, const char *lib);
+	RBinWriteScnResize scn_resize;
+	RBinWriteScnPerms scn_perms;
+	RBinWriteRpathDel rpath_del;
+	RBinWriteEntry entry;
+	RBinWriteAddLib addlib;
 } RBinWrite;
 
 typedef int (*RBinGetOffset)(RBin *bin, int type, int idx);

libr/main/rabin2.c

@@ -10,7 +10,7 @@ typedef struct rabin2_state_t {
 static int rabin_show_help(int v) {
 	printf ("Usage: rabin2 [-AcdeEghHiIjlLMqrRsSUvVxzZ] [-@ at] [-a arch] [-b bits] [-B addr]\n"
 		"              [-C F:C:D] [-f str] [-m addr] [-n str] [-N m:M] [-P[-P] pdb]\n"
-		"              [-o str] [-O str] [-k query] [-D lang mangledsymbol] file\n");
+		"              [-o str] [-O help] [-k query] [-D lang mangledsymbol] file\n");
 	if (v) {
 		printf (
 		" -@ [addr]       show section, symbol or import at addr\n"

test/db/formats/dwarf

@@ -721,20 +721,20 @@ colu: 12
 addr: 0x00001149
 EOF
 EXPECT_ERR=<<EOF
-DEBUG: [cbin.c:3368] (section .dynstr) Css 141 @ 0x480
-DEBUG: [cbin.c:3368] (section .rela.dyn) Cd 8[24] @ 0x550
-DEBUG: [cbin.c:3368] (section .rela.plt) Cd 8[3] @ 0x610
-DEBUG: [cbin.c:3368] (section .init_array) Cd 8[1] @ 0x3db8
-DEBUG: [cbin.c:3368] (section .fini_array) Cd 8[1] @ 0x3dc0
-DEBUG: [cbin.c:3368] (section .dynamic) Cd 8[62] @ 0x3dc8
-DEBUG: [cbin.c:3368] (section .got) Cd 8[9] @ 0x3fb8
-DEBUG: [cbin.c:3368] (section .dynstr) Css 141 @ 0x480
-DEBUG: [cbin.c:3368] (section .rela.dyn) Cd 8[24] @ 0x550
-DEBUG: [cbin.c:3368] (section .rela.plt) Cd 8[3] @ 0x610
-DEBUG: [cbin.c:3368] (section .init_array) Cd 8[1] @ 0x3db8
-DEBUG: [cbin.c:3368] (section .fini_array) Cd 8[1] @ 0x3dc0
-DEBUG: [cbin.c:3368] (section .dynamic) Cd 8[62] @ 0x3dc8
-DEBUG: [cbin.c:3368] (section .got) Cd 8[9] @ 0x3fb8
+DEBUG: [cbin.c:3375] (section .dynstr) Css 141 @ 0x480
+DEBUG: [cbin.c:3375] (section .rela.dyn) Cd 8[24] @ 0x550
+DEBUG: [cbin.c:3375] (section .rela.plt) Cd 8[3] @ 0x610
+DEBUG: [cbin.c:3375] (section .init_array) Cd 8[1] @ 0x3db8
+DEBUG: [cbin.c:3375] (section .fini_array) Cd 8[1] @ 0x3dc0
+DEBUG: [cbin.c:3375] (section .dynamic) Cd 8[62] @ 0x3dc8
+DEBUG: [cbin.c:3375] (section .got) Cd 8[9] @ 0x3fb8
+DEBUG: [cbin.c:3375] (section .dynstr) Css 141 @ 0x480
+DEBUG: [cbin.c:3375] (section .rela.dyn) Cd 8[24] @ 0x550
+DEBUG: [cbin.c:3375] (section .rela.plt) Cd 8[3] @ 0x610
+DEBUG: [cbin.c:3375] (section .init_array) Cd 8[1] @ 0x3db8
+DEBUG: [cbin.c:3375] (section .fini_array) Cd 8[1] @ 0x3dc0
+DEBUG: [cbin.c:3375] (section .dynamic) Cd 8[62] @ 0x3dc8
+DEBUG: [cbin.c:3375] (section .got) Cd 8[9] @ 0x3fb8
 WARN: [cbin.c:1904] Relocs has not been applied. Please use `-e bin.relocs.apply=true` or `-e bin.cache=true` next time
 DEBUG: [cbin.c:2620] Cannot resolve symbol address __libc_start_main
 DEBUG: [cbin.c:2620] Cannot resolve symbol address _ITM_deregisterTMCloneTable