klibc-bot for Ben Hutchings
2021-Apr-30 00:00 UTC
[klibc] [klibc:master] cpio: Fix possible crash on 64-bit systems
Commit-ID: 2e48a12ab1e30d43498c2d53e878a11a1b5102d5 Gitweb: http://git.kernel.org/?p=libs/klibc/klibc.git;a=commit;h=2e48a12ab1e30d43498c2d53e878a11a1b5102d5 Author: Ben Hutchings <ben at decadent.org.uk> AuthorDate: Wed, 28 Apr 2021 19:46:47 +0200 Committer: Ben Hutchings <ben at decadent.org.uk> CommitDate: Thu, 29 Apr 2021 16:03:19 +0200 [klibc] cpio: Fix possible crash on 64-bit systems copyin_link() tries to allocate (unsigned int)c_filesize + 1 bytes. If c_filesize == UINT_MAX, this works out as 0 bytes, resulting in a null pointer and a subsequent SIGSEGV. The previous commit made this impossible on 32-bit systems. CVE-2021-31871 Signed-off-by: Ben Hutchings <ben at decadent.org.uk> --- usr/utils/cpio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/usr/utils/cpio.c b/usr/utils/cpio.c index ac481310..9b0b6ae9 100644 --- a/usr/utils/cpio.c +++ b/usr/utils/cpio.c @@ -832,7 +832,7 @@ static void copyin_link(struct new_cpio_header *file_hdr, int in_file_des) char *link_name = NULL; /* Name of hard and symbolic links. */ int res; /* Result of various function calls. */ - link_name = (char *)xmalloc((unsigned int)file_hdr->c_filesize + 1); + link_name = (char *)xmalloc(file_hdr->c_filesize + 1); link_name[file_hdr->c_filesize] = '\0'; tape_buffered_read(link_name, in_file_des, file_hdr->c_filesize); tape_skip_padding(in_file_des, file_hdr->c_filesize);