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| author | Christoph Hellwig <hch@lst.de> | 2019-06-13 09:09:02 +0200 |
|---|---|---|
| committer | Greg Ungerer <gerg@kernel.org> | 2019-06-24 09:16:47 +1000 |
| commit | a2357223c50a784ae144c8398683551252bcd61d (patch) | |
| tree | d5ea178771a9f356b6660235a3c2682a0d7eba42 /fs/binfmt_flat.c | |
| parent | a445d988b4790e06bb94e927e740017675d7e700 (diff) | |
| download | linux-a2357223c50a784ae144c8398683551252bcd61d.tar.gz | |
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: Christoph Hellwig <hch@lst.de> Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Diffstat (limited to 'fs/binfmt_flat.c')
| -rw-r--r-- | fs/binfmt_flat.c | 20 |
1 files changed, 8 insertions, 12 deletions
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index ccd9843e979e..80d902fb46e3 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -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)); @@ -653,8 +649,9 @@ static int load_flat_file(struct linux_binprm *bprm, (text_len + full_data - sizeof(struct flat_hdr)), 0); - memmove((void *) datapos, (void *) realdatastart, - full_data); + if (datapos != realdatastart) + memmove((void *)datapos, (void *)realdatastart, + full_data); #else /* * This is used on MMU systems mainly for testing. @@ -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; } } |