Commit a2357223 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Greg Ungerer
Browse files

binfmt_flat: don't offset the data start 



Ever since the initial commit of the binfmt_flat shared library
support back in the bitkeeper days we've offset the actual in-memory
.data start by one field per possible shared library, or 1 in case
shared library support isn't enabled.  I can't find anything in the
loader that actually makes use of it, nor was it present before
shared library support it.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarGreg Ungerer <gerg@linux-m68k.org>
parent a445d988

fs/binfmt_flat.c

+8 −12
Original line number Diff line number Diff line
@@ -573,7 +573,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
			goto err;

		}



		len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);

		len = data_len + extra;

		len = PAGE_ALIGN(len);

		realdatastart = vm_mmap(NULL, 0, len,

			PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
@@ -587,9 +587,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
			vm_munmap(textpos, text_len);

			goto err;

		}

		datapos = ALIGN(realdatastart +

				MAX_SHARED_LIBS * sizeof(unsigned long),

				FLAT_DATA_ALIGN);

		datapos = ALIGN(realdatastart, FLAT_DATA_ALIGN);



		pr_debug("Allocated data+bss+stack (%u bytes): %lx\n",

			 data_len + bss_len + stack_len, datapos);
@@ -619,7 +617,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
		memp_size = len;

	} else {



		len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(u32);

		len = text_len + data_len + extra;

		len = PAGE_ALIGN(len);

		textpos = vm_mmap(NULL, 0, len,

			PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
@@ -634,9 +632,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
		}



		realdatastart = textpos + ntohl(hdr->data_start);

		datapos = ALIGN(realdatastart +

				MAX_SHARED_LIBS * sizeof(u32),

				FLAT_DATA_ALIGN);

		datapos = ALIGN(realdatastart, FLAT_DATA_ALIGN);



		reloc = (__be32 __user *)

			(datapos + (ntohl(hdr->reloc_start) - text_len));
@@ -653,6 +649,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
					 (text_len + full_data

						  - sizeof(struct flat_hdr)),

					 0);

			if (datapos != realdatastart)

				memmove((void *)datapos, (void *)realdatastart,

						full_data);

#else
@@ -710,8 +707,7 @@ static int load_flat_file(struct linux_binprm *bprm, 
		if (IS_ERR_VALUE(result)) {

			ret = result;

			pr_err("Unable to read code+data+bss, errno %d\n", ret);

			vm_munmap(textpos, text_len + data_len + extra +

				MAX_SHARED_LIBS * sizeof(u32));

			vm_munmap(textpos, text_len + data_len + extra);

			goto err;

		}

	}

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