From 81e25b7c91efcc3ff54605b11859375a5c885c8b Mon Sep 17 00:00:00 2001 From: Erik Kurzinger Date: Wed, 23 May 2018 12:04:39 +0100 Subject: [PATCH] Improve File I/O overflow detection in gdbserver (PR server/23198) Currently, the function used by gdbserver to parse integers from received File I/O commands will detect overflow and fail for any value over 0xfffffff. Among other things, this has the effect of limiting the file offsets for reading or writing to about 268MB which can be insufficient for particularly large libraries. This change allows the parsing of integers up to the true maximum positive value of 0x7fffffff, increasing the file size limit to about 2GB. gdb/gdbserver/ChangeLog: 2018-05-23 Erik Kurzinger PR server/23198 * hostio.c (require_int): Do not report overflow for integers between 0xfffffff and 0x7fffffff. --- gdb/gdbserver/ChangeLog | 6 ++++++ gdb/gdbserver/hostio.c | 13 +++++++++---- 2 files changed, 15 insertions(+), 4 deletions(-) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 54a07b8f30c..7aa59467ac3 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,9 @@ +2018-05-23 Erik Kurzinger + + PR server/23198 + * hostio.c (require_int): Do not report overflow for integers + between 0xfffffff and 0x7fffffff. + 2018-05-22 Maciej W. Rozycki * linux-mips-low.c [HAVE_PTRACE_GETREGS] (mips_collect_register) diff --git a/gdb/gdbserver/hostio.c b/gdb/gdbserver/hostio.c index d2b5a71bade..c621edfef56 100644 --- a/gdb/gdbserver/hostio.c +++ b/gdb/gdbserver/hostio.c @@ -96,22 +96,27 @@ static int require_int (char **pp, int *value) { char *p; - int count; + int count, firstdigit; p = *pp; *value = 0; count = 0; + firstdigit = -1; while (*p && *p != ',') { int nib; - /* Don't allow overflow. */ - if (count >= 7) + if (safe_fromhex (p[0], &nib)) return -1; - if (safe_fromhex (p[0], &nib)) + if (firstdigit == -1) + firstdigit = nib; + + /* Don't allow overflow. */ + if (count >= 8 || (count == 7 && firstdigit >= 0x8)) return -1; + *value = *value * 16 + nib; p++; count++; -- 2.30.2