From 228c8f4be0c428369ec6b68e25696863d1e62ed7 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Thu, 19 Dec 2019 21:46:01 +1030 Subject: [PATCH] xcoff slurp_armap bounds checking "count * 8 >= size" might overflow, "count >= size / 8" doesn't. * coff-rs6000.c (_bfd_xcoff_slurp_armap): Don't overflow when checking symbol count against section size. Guard against strlen running off end of buffer by allocating one more byte and zeroing. * coff64-rs6000.c (xcoff64_slurp_armap): Likewise. --- bfd/ChangeLog | 7 +++++++ bfd/coff-rs6000.c | 26 ++++++++++++++++++++++---- bfd/coff64-rs6000.c | 13 +++++++++++-- 3 files changed, 40 insertions(+), 6 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 302ee5ec85..dc264de3cc 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,10 @@ +2019-12-18 Alan Modra + + * coff-rs6000.c (_bfd_xcoff_slurp_armap): Don't overflow when + checking symbol count against section size. Guard against strlen + running off end of buffer by allocating one more byte and zeroing. + * coff64-rs6000.c (xcoff64_slurp_armap): Likewise. + 2019-12-18 Alan Modra * elf32-ppc.c (ppc_elf_get_synthetic_symtab): Use size_t for vars. diff --git a/bfd/coff-rs6000.c b/bfd/coff-rs6000.c index 86cf9e3e2a..995a88a309 100644 --- a/bfd/coff-rs6000.c +++ b/bfd/coff-rs6000.c @@ -1260,18 +1260,27 @@ _bfd_xcoff_slurp_armap (bfd *abfd) return FALSE; GET_VALUE_IN_FIELD (sz, hdr.size, 10); + if (sz == (bfd_size_type) -1) + { + bfd_set_error (bfd_error_no_memory); + return FALSE; + } /* Read in the entire symbol table. */ - contents = (bfd_byte *) bfd_alloc (abfd, sz); + contents = (bfd_byte *) bfd_alloc (abfd, sz + 1); if (contents == NULL) return FALSE; if (bfd_bread (contents, sz, abfd) != sz) return FALSE; + /* Ensure strings are NULL terminated so we don't wander off the + end of the buffer. */ + contents[sz] = 0; + /* The symbol table starts with a four byte count. */ c = H_GET_32 (abfd, contents); - if (c * 4 >= sz) + if (c >= sz / 4) { bfd_set_error (bfd_error_bad_value); return FALSE; @@ -1315,18 +1324,27 @@ _bfd_xcoff_slurp_armap (bfd *abfd) return FALSE; GET_VALUE_IN_FIELD (sz, hdr.size, 10); + if (sz == (bfd_size_type) -1) + { + bfd_set_error (bfd_error_no_memory); + return FALSE; + } /* Read in the entire symbol table. */ - contents = (bfd_byte *) bfd_alloc (abfd, sz); + contents = (bfd_byte *) bfd_alloc (abfd, sz + 1); if (contents == NULL) return FALSE; if (bfd_bread (contents, sz, abfd) != sz) return FALSE; + /* Ensure strings are NULL terminated so we don't wander off the + end of the buffer. */ + contents[sz] = 0; + /* The symbol table starts with an eight byte count. */ c = H_GET_64 (abfd, contents); - if (c * 8 >= sz) + if (c >= sz / 8) { bfd_set_error (bfd_error_bad_value); return FALSE; diff --git a/bfd/coff64-rs6000.c b/bfd/coff64-rs6000.c index 091da1fd5e..4db61e5706 100644 --- a/bfd/coff64-rs6000.c +++ b/bfd/coff64-rs6000.c @@ -1933,18 +1933,27 @@ xcoff64_slurp_armap (bfd *abfd) return FALSE; sz = bfd_scan_vma (hdr.size, (const char **) NULL, 10); + if (sz == (bfd_size_type) -1) + { + bfd_set_error (bfd_error_no_memory); + return FALSE; + } /* Read in the entire symbol table. */ - contents = (bfd_byte *) bfd_alloc (abfd, sz); + contents = (bfd_byte *) bfd_alloc (abfd, sz + 1); if (contents == NULL) return FALSE; if (bfd_bread (contents, sz, abfd) != sz) return FALSE; + /* Ensure strings are NULL terminated so we don't wander off the end + of the buffer. */ + contents[sz] = 0; + /* The symbol table starts with an eight byte count. */ c = H_GET_64 (abfd, contents); - if (c * 8 >= sz) + if (c >= sz / 8) { bfd_set_error (bfd_error_bad_value); return FALSE; -- 2.34.1