From b920bc37223df1213180ec0b13eb0828c015d34f Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Mon, 25 Oct 2021 10:15:59 +1030 Subject: [PATCH] asan: evax_bfd_print_image buffer overflow * vms-alpha.c (evax_bfd_print_image): Sanity check printing of "image activator fixup" section. (evax_bfd_print_relocation_records): Sanity check buffer offsets. (evax_bfd_print_address_fixups): Likewise. (evax_bfd_print_reference_fixups): Likewise. --- bfd/vms-alpha.c | 93 +++++++++++++++++++++++++++---------------------- 1 file changed, 51 insertions(+), 42 deletions(-) diff --git a/bfd/vms-alpha.c b/bfd/vms-alpha.c index 83a103ae63b..0baca52febd 100644 --- a/bfd/vms-alpha.c +++ b/bfd/vms-alpha.c @@ -6754,34 +6754,35 @@ evax_bfd_print_eobj (struct bfd *abfd, FILE *file) } static void -evax_bfd_print_relocation_records (FILE *file, const unsigned char *rel, +evax_bfd_print_relocation_records (FILE *file, const unsigned char *buf, + size_t buf_size, size_t off, unsigned int stride) { - while (1) + while (off <= buf_size - 8) { unsigned int base; unsigned int count; unsigned int j; - count = bfd_getl32 (rel + 0); + count = bfd_getl32 (buf + off + 0); if (count == 0) break; - base = bfd_getl32 (rel + 4); + base = bfd_getl32 (buf + off + 4); /* xgettext:c-format */ fprintf (file, _(" bitcount: %u, base addr: 0x%08x\n"), count, base); - rel += 8; - for (j = 0; count > 0; j += 4, count -= 32) + off += 8; + for (j = 0; count > 0 && off <= buf_size - 4; j += 4, count -= 32) { unsigned int k; unsigned int n = 0; unsigned int val; - val = bfd_getl32 (rel); - rel += 4; + val = bfd_getl32 (buf + off); + off += 4; /* xgettext:c-format */ fprintf (file, _(" bitmap: 0x%08x (count: %u):\n"), val, count); @@ -6806,60 +6807,62 @@ evax_bfd_print_relocation_records (FILE *file, const unsigned char *rel, } static void -evax_bfd_print_address_fixups (FILE *file, const unsigned char *rel) +evax_bfd_print_address_fixups (FILE *file, const unsigned char *buf, + size_t buf_size, size_t off) { - while (1) + while (off <= buf_size - 8) { unsigned int j; unsigned int count; - count = bfd_getl32 (rel + 0); + count = bfd_getl32 (buf + off + 0); if (count == 0) return; /* xgettext:c-format */ fprintf (file, _(" image %u (%u entries)\n"), - (unsigned)bfd_getl32 (rel + 4), count); - rel += 8; - for (j = 0; j < count; j++) + (unsigned) bfd_getl32 (buf + off + 4), count); + off += 8; + for (j = 0; j < count && off <= buf_size - 8; j++) { /* xgettext:c-format */ fprintf (file, _(" offset: 0x%08x, val: 0x%08x\n"), - (unsigned)bfd_getl32 (rel + 0), - (unsigned)bfd_getl32 (rel + 4)); - rel += 8; + (unsigned) bfd_getl32 (buf + off + 0), + (unsigned) bfd_getl32 (buf + off + 4)); + off += 8; } } } static void -evax_bfd_print_reference_fixups (FILE *file, const unsigned char *rel) +evax_bfd_print_reference_fixups (FILE *file, const unsigned char *buf, + size_t buf_size, size_t off) { unsigned int count; - while (1) + while (off <= buf_size - 8) { unsigned int j; unsigned int n = 0; - count = bfd_getl32 (rel + 0); + count = bfd_getl32 (buf + off + 0); if (count == 0) break; /* xgettext:c-format */ fprintf (file, _(" image %u (%u entries), offsets:\n"), - (unsigned)bfd_getl32 (rel + 4), count); - rel += 8; - for (j = 0; j < count; j++) + (unsigned) bfd_getl32 (buf + off + 4), count); + off += 8; + for (j = 0; j < count && off <= buf_size - 4; j++) { if (n == 0) fputs (" ", file); - fprintf (file, _(" 0x%08x"), (unsigned)bfd_getl32 (rel)); + fprintf (file, _(" 0x%08x"), (unsigned) bfd_getl32 (buf + off)); n++; if (n == 7) { fputs ("\n", file); n = 0; } - rel += 4; + off += 4; } if (n) fputs ("\n", file); @@ -8111,7 +8114,7 @@ evax_bfd_print_image (bfd *abfd, FILE *file) fprintf (file, _("Global symbol table:\n")); evax_bfd_print_eobj (abfd, file); } - if (eiaf_vbn != 0) + if (eiaf_vbn != 0 && eiaf_size >= sizeof (struct vms_eiaf)) { unsigned char *buf; struct vms_eiaf *eiaf; @@ -8183,12 +8186,14 @@ evax_bfd_print_image (bfd *abfd, FILE *file) if (shlstoff) { - struct vms_shl *shl = (struct vms_shl *)(buf + shlstoff); unsigned int j; fprintf (file, _(" Shareable images:\n")); - for (j = 0; j < shrimgcnt; j++, shl++) + for (j = 0; + j < shrimgcnt && shlstoff <= eiaf_size - sizeof (struct vms_shl); + j++, shlstoff += sizeof (struct vms_shl)) { + struct vms_shl *shl = (struct vms_shl *) (buf + shlstoff); fprintf (file, /* xgettext:c-format */ _(" %u: size: %u, flags: 0x%02x, name: %.*s\n"), @@ -8199,50 +8204,54 @@ evax_bfd_print_image (bfd *abfd, FILE *file) if (qrelfixoff != 0) { fprintf (file, _(" quad-word relocation fixups:\n")); - evax_bfd_print_relocation_records (file, buf + qrelfixoff, 8); + evax_bfd_print_relocation_records (file, buf, eiaf_size, + qrelfixoff, 8); } if (lrelfixoff != 0) { fprintf (file, _(" long-word relocation fixups:\n")); - evax_bfd_print_relocation_records (file, buf + lrelfixoff, 4); + evax_bfd_print_relocation_records (file, buf, eiaf_size, + lrelfixoff, 4); } if (qdotadroff != 0) { fprintf (file, _(" quad-word .address reference fixups:\n")); - evax_bfd_print_address_fixups (file, buf + qdotadroff); + evax_bfd_print_address_fixups (file, buf, eiaf_size, qdotadroff); } if (ldotadroff != 0) { fprintf (file, _(" long-word .address reference fixups:\n")); - evax_bfd_print_address_fixups (file, buf + ldotadroff); + evax_bfd_print_address_fixups (file, buf, eiaf_size, ldotadroff); } if (codeadroff != 0) { fprintf (file, _(" Code Address Reference Fixups:\n")); - evax_bfd_print_reference_fixups (file, buf + codeadroff); + evax_bfd_print_reference_fixups (file, buf, eiaf_size, codeadroff); } if (lpfixoff != 0) { fprintf (file, _(" Linkage Pairs Reference Fixups:\n")); - evax_bfd_print_reference_fixups (file, buf + lpfixoff); + evax_bfd_print_reference_fixups (file, buf, eiaf_size, lpfixoff); } - if (chgprtoff) + if (chgprtoff && chgprtoff <= eiaf_size - 4) { - unsigned int count = (unsigned)bfd_getl32 (buf + chgprtoff); - struct vms_eicp *eicp = (struct vms_eicp *)(buf + chgprtoff + 4); + unsigned int count = (unsigned) bfd_getl32 (buf + chgprtoff); unsigned int j; fprintf (file, _(" Change Protection (%u entries):\n"), count); - for (j = 0; j < count; j++, eicp++) + for (j = 0, chgprtoff += 4; + j < count && chgprtoff <= eiaf_size - sizeof (struct vms_eicp); + j++, chgprtoff += sizeof (struct vms_eicp)) { + struct vms_eicp *eicp = (struct vms_eicp *) (buf + chgprtoff); unsigned int prot = bfd_getl32 (eicp->newprt); fprintf (file, /* xgettext:c-format */ _(" base: 0x%08x %08x, size: 0x%08x, prot: 0x%08x "), - (unsigned)bfd_getl32 (eicp->baseva + 4), - (unsigned)bfd_getl32 (eicp->baseva + 0), - (unsigned)bfd_getl32 (eicp->size), - (unsigned)bfd_getl32 (eicp->newprt)); + (unsigned) bfd_getl32 (eicp->baseva + 4), + (unsigned) bfd_getl32 (eicp->baseva + 0), + (unsigned) bfd_getl32 (eicp->size), + (unsigned) bfd_getl32 (eicp->newprt)); switch (prot) { case PRT__C_NA: -- 2.30.2