From: Alexey Dobriyan <adobriyan@xxxxxxxxx> Subject: elf: fix NT_FILE integer overflow If vm.max_map_count bumped above 2^26 (67+ mil) and system has enough RAM to allocate all the VMAs (~12.8 GB on Fedora 27 with 200-byte VMAs), then it should be possible to overflow 32-bit "size", pass paranoia check, allocate very little vmalloc space and oops while writing into vmalloc guard page... But I didn't test this, only coredump of regular process. Link: http://lkml.kernel.org/r/20180112203427.GA9109@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/binfmt_elf.c | 2 ++ 1 file changed, 2 insertions(+) diff -puN fs/binfmt_elf.c~elf-fix-nt_file-integer-overflow fs/binfmt_elf.c --- a/fs/binfmt_elf.c~elf-fix-nt_file-integer-overflow +++ a/fs/binfmt_elf.c @@ -1599,6 +1599,8 @@ static int fill_files_note(struct memelf /* *Estimated* file count and total data size needed */ count = current->mm->map_count; + if (count > UINT_MAX / 64) + return -EINVAL; size = count * 64; names_ofs = (2 + 3 * count) * sizeof(data[0]); _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
