new helper: read_code()

switch binfmts that use ->read() to that (and to kernel_read()
in several cases in binfmt_flat - sure, it's nommu, but still,
doing ->read() into kmalloc'ed buffer...)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

4 files changed, 35 insertions, 43 deletions

diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index bbc8f88..b23253d 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -287,15 +287,12 @@ static int load_aout_binary(struct linux_binprm * bprm)
 			return error;
 		}
 
-		error = bprm->file->f_op->read(bprm->file,
-			  (char __user *)text_addr,
-			  ex.a_text+ex.a_data, &pos);
+		error = read_code(bprm->file, text_addr, pos,
+				  ex.a_text+ex.a_data);
 		if ((signed long)error < 0) {
 			send_sig(SIGKILL, current, 0);
 			return error;
 		}
-			 
-		flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
 	} else {
 		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
 		    (N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
@@ -311,14 +308,9 @@ static int load_aout_binary(struct linux_binprm * bprm)
 		}
 
 		if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
-			loff_t pos = fd_offset;
 			vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
-			bprm->file->f_op->read(bprm->file,
-					(char __user *)N_TXTADDR(ex),
-					ex.a_text+ex.a_data, &pos);
-			flush_icache_range((unsigned long) N_TXTADDR(ex),
-					   (unsigned long) N_TXTADDR(ex) +
-					   ex.a_text+ex.a_data);
+			read_code(bprm->file, N_TXTADDR(ex), fd_offset,
+				  ex.a_text + ex.a_data);
 			goto beyond_if;
 		}
 
@@ -397,8 +389,6 @@ static int load_aout_library(struct file *file)
 	start_addr =  ex.a_entry & 0xfffff000;
 
 	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
-		loff_t pos = N_TXTOFF(ex);
-
 		if (printk_ratelimit())
 		{
 			printk(KERN_WARNING 
@@ -407,11 +397,8 @@ static int load_aout_library(struct file *file)
 		}
 		vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
 		
-		file->f_op->read(file, (char __user *)start_addr,
-			ex.a_text + ex.a_data, &pos);
-		flush_icache_range((unsigned long) start_addr,
-				   (unsigned long) start_addr + ex.a_text + ex.a_data);
-
+		read_code(file, start_addr, N_TXTOFF(ex),
+			  ex.a_text + ex.a_data);
 		retval = 0;
 		goto out;
 	}
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 9c13e02..2711d99 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -926,7 +926,6 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
 	struct elf32_fdpic_loadseg *seg;
 	struct elf32_phdr *phdr;
 	unsigned long load_addr, base = ULONG_MAX, top = 0, maddr = 0, mflags;
-	loff_t fpos;
 	int loop, ret;
 
 	load_addr = params->load_addr;
@@ -964,14 +963,12 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
 		if (params->phdrs[loop].p_type != PT_LOAD)
 			continue;
 
-		fpos = phdr->p_offset;
-
 		seg->addr = maddr + (phdr->p_vaddr - base);
 		seg->p_vaddr = phdr->p_vaddr;
 		seg->p_memsz = phdr->p_memsz;
 
-		ret = file->f_op->read(file, (void *) seg->addr,
-				       phdr->p_filesz, &fpos);
+		ret = read_code(file, seg->addr, phdr->p_offset,
+				       phdr->p_filesz);
 		if (ret < 0)
 			return ret;
 
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 2036d21..d50bbe5 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -207,11 +207,12 @@ static int decompress_exec(
 
 	/* Read in first chunk of data and parse gzip header. */
 	fpos = offset;
-	ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
+	ret = kernel_read(bprm->file, offset, buf, LBUFSIZE);
 
 	strm.next_in = buf;
 	strm.avail_in = ret;
 	strm.total_in = 0;
+	fpos += ret;
 
 	retval = -ENOEXEC;
 
@@ -277,7 +278,7 @@ static int decompress_exec(
 	}
 
 	while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
-		ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
+		ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE);
 		if (ret <= 0)
 			break;
 		len -= ret;
@@ -285,6 +286,7 @@ static int decompress_exec(
 		strm.next_in = buf;
 		strm.avail_in = ret;
 		strm.total_in = 0;
+		fpos += ret;
 	}
 
 	if (ret < 0) {
@@ -428,6 +430,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 	unsigned long textpos = 0, datapos = 0, result;
 	unsigned long realdatastart = 0;
 	unsigned long text_len, data_len, bss_len, stack_len, flags;
+	unsigned long full_data;
 	unsigned long len, memp = 0;
 	unsigned long memp_size, extra, rlim;
 	unsigned long *reloc = 0, *rp;
@@ -451,6 +454,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 	relocs    = ntohl(hdr->reloc_count);
 	flags     = ntohl(hdr->flags);
 	rev       = ntohl(hdr->rev);
+	full_data = data_len + relocs * sizeof(unsigned long);
 
 	if (strncmp(hdr->magic, "bFLT", 4)) {
 		/*
@@ -577,12 +581,12 @@ static int load_flat_file(struct linux_binprm * bprm,
 #ifdef CONFIG_BINFMT_ZFLAT
 		if (flags & FLAT_FLAG_GZDATA) {
 			result = decompress_exec(bprm, fpos, (char *) datapos, 
-						 data_len + (relocs * sizeof(unsigned long)), 0);
+						 full_data, 0);
 		} else
 #endif
 		{
-			result = bprm->file->f_op->read(bprm->file, (char *) datapos,
-					data_len + (relocs * sizeof(unsigned long)), &fpos);
+			result = read_code(bprm->file, datapos, fpos,
+					full_data);
 		}
 		if (IS_ERR_VALUE(result)) {
 			printk("Unable to read data+bss, errno %d\n", (int)-result);
@@ -627,30 +631,25 @@ static int load_flat_file(struct linux_binprm * bprm,
 		if (flags & FLAT_FLAG_GZIP) {
 			result = decompress_exec(bprm, sizeof (struct flat_hdr),
 					 (((char *) textpos) + sizeof (struct flat_hdr)),
-					 (text_len + data_len + (relocs * sizeof(unsigned long))
+					 (text_len + full_data
 						  - sizeof (struct flat_hdr)),
 					 0);
 			memmove((void *) datapos, (void *) realdatastart,
-					data_len + (relocs * sizeof(unsigned long)));
+					full_data);
 		} else if (flags & FLAT_FLAG_GZDATA) {
-			fpos = 0;
-			result = bprm->file->f_op->read(bprm->file,
-					(char *) textpos, text_len, &fpos);
+			result = read_code(bprm->file, textpos, 0, text_len);
 			if (!IS_ERR_VALUE(result))
 				result = decompress_exec(bprm, text_len, (char *) datapos,
-						 data_len + (relocs * sizeof(unsigned long)), 0);
+						 full_data, 0);
 		}
 		else
 #endif
 		{
-			fpos = 0;
-			result = bprm->file->f_op->read(bprm->file,
-					(char *) textpos, text_len, &fpos);
-			if (!IS_ERR_VALUE(result)) {
-				fpos = ntohl(hdr->data_start);
-				result = bprm->file->f_op->read(bprm->file, (char *) datapos,
-					data_len + (relocs * sizeof(unsigned long)), &fpos);
-			}
+			result = read_code(bprm->file, textpos, 0, text_len);
+			if (!IS_ERR_VALUE(result))
+				result = read_code(bprm->file, datapos,
+						   ntohl(hdr->data_start),
+						   full_data);
 		}
 		if (IS_ERR_VALUE(result)) {
 			printk("Unable to read code+data+bss, errno %d\n",(int)-result);
diff --git a/fs/exec.c b/fs/exec.c
index a96a488..77dc909 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -802,6 +802,15 @@ int kernel_read(struct file *file, loff_t offset,
 
 EXPORT_SYMBOL(kernel_read);
 
+ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
+{
+	ssize_t res = file->f_op->read(file, (void __user *)addr, len, &pos);
+	if (res > 0)
+		flush_icache_range(addr, addr + len);
+	return res;
+}
+EXPORT_SYMBOL(read_code);
+
 static int exec_mmap(struct mm_struct *mm)
 {
 	struct task_struct *tsk;