From 8d17c53b8dfc23b456e30c8f21d46dbcd55324ae Mon Sep 17 00:00:00 2001 From: Nick Clifton Date: Thu, 30 Mar 2023 11:04:53 +0100 Subject: [PATCH] Fix an illegal memory access triggered by parsing corrupt DWARF info. PR 30284 * dwarf.c (read_and_display_attr_value): Detect and ignore negative base values. --- binutils/ChangeLog | 6 ++++++ binutils/dwarf.c | 32 +++++++++++++++++++++++++++++--- 2 files changed, 35 insertions(+), 3 deletions(-) diff --git a/binutils/ChangeLog b/binutils/ChangeLog index a6932cba144..0794bed00d3 100644 --- a/binutils/ChangeLog +++ b/binutils/ChangeLog @@ -1,3 +1,9 @@ +2023-03-30 Nick Clifton + + PR 30284 + * dwarf.c (read_and_display_attr_value): Detect and ignore + negative base values. + 2023-03-23 Frederic Cambus * readelf.c (get_segment_type): Handle PT_OPENBSD_MUTABLE segment diff --git a/binutils/dwarf.c b/binutils/dwarf.c index 89b0b80d949..d6fc9fe991c 100644 --- a/binutils/dwarf.c +++ b/binutils/dwarf.c @@ -2802,7 +2802,7 @@ read_and_display_attr_value (unsigned long attribute, break; default: - warn (_("Unrecognized form: %#lx\n"), form); + warn (_("Unrecognized form: %#lx"), form); /* What to do? Consume a byte maybe? */ ++data; break; @@ -2820,22 +2820,48 @@ read_and_display_attr_value (unsigned long attribute, "(%#" PRIx64 " and %#" PRIx64 ")"), debug_info_p->cu_offset, debug_info_p->loclists_base, uvalue); + svalue = uvalue; + if (svalue < 0) + { + warn (_("CU @ %#" PRIx64 " has has a negative loclists_base " + "value of %#" PRIx64 " - treating as zero"), + debug_info_p->cu_offset, svalue); + uvalue = 0; + } debug_info_p->loclists_base = uvalue; break; + case DW_AT_rnglists_base: if (debug_info_p->rnglists_base) warn (_("CU @ %#" PRIx64 " has multiple rnglists_base values " "(%#" PRIx64 " and %#" PRIx64 ")"), debug_info_p->cu_offset, debug_info_p->rnglists_base, uvalue); + svalue = uvalue; + if (svalue < 0) + { + warn (_("CU @ %#" PRIx64 " has has a negative rnglists_base " + "value of %#" PRIx64 " - treating as zero"), + debug_info_p->cu_offset, svalue); + uvalue = 0; + } debug_info_p->rnglists_base = uvalue; break; + case DW_AT_str_offsets_base: if (debug_info_p->str_offsets_base) warn (_("CU @ %#" PRIx64 " has multiple str_offsets_base values " "%#" PRIx64 " and %#" PRIx64 ")"), debug_info_p->cu_offset, debug_info_p->str_offsets_base, uvalue); + svalue = uvalue; + if (svalue < 0) + { + warn (_("CU @ %#" PRIx64 " has has a negative stroffsets_base " + "value of %#" PRIx64 " - treating as zero"), + debug_info_p->cu_offset, svalue); + uvalue = 0; + } debug_info_p->str_offsets_base = uvalue; break; @@ -8245,7 +8271,7 @@ display_debug_ranges (struct dwarf_section *section, } introduce (section, false); - + if (is_rnglists) return display_debug_rnglists (section); @@ -8324,7 +8350,7 @@ display_debug_ranges (struct dwarf_section *section, } next = section_begin + offset + debug_info_p->rnglists_base; - + /* If multiple DWARF entities reference the same range then we will have multiple entries in the `range_entries' list for the same offset. Thanks to the sort above these will all be consecutive in -- 2.30.2