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 bbc8f8827eac..b23253df8756 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 9c13e023e2b7..2711d9901632 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 2036d21baaef..d50bbe59da1e 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 a96a4885bbbf..77dc9096440f 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;