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>

1 files changed, 18 insertions, 19 deletions

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);