From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2126) id 8971A385F024; Fri, 20 Mar 2020 14:36:39 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 8971A385F024 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tom Tromey To: gdb-cvs@sourceware.org Subject: [binutils-gdb] Avoid stringop-truncation errors X-Act-Checkin: binutils-gdb X-Git-Author: Tom Tromey X-Git-Refname: refs/heads/master X-Git-Oldrev: 1773be9ea2207d42442222e6dc3c8fdbe638e28e X-Git-Newrev: f67210ff1c4200ea668189d086c6b39145cd876f Message-Id: <20200320143639.8971A385F024@sourceware.org> Date: Fri, 20 Mar 2020 14:36:39 +0000 (GMT) X-BeenThere: gdb-cvs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Mar 2020 14:36:39 -0000 https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f67210ff1c4200ea668189d086c6b39145cd876f commit f67210ff1c4200ea668189d086c6b39145cd876f Author: Tom Tromey Date: Fri Mar 20 07:30:13 2020 -0600 Avoid stringop-truncation errors I configured with -fsanitize=address and built gdb. linux-tdep.c and ada-tasks.c failed to build due to some stringop-truncation errors, e.g.: In function ‘char* strncpy(char*, const char*, size_t)’, inlined from ‘int linux_fill_prpsinfo(elf_internal_linux_prpsinfo*)’ at ../../binutils-gdb/gdb/linux-tdep.c:1742:11, inlined from ‘char* linux_make_corefile_notes(gdbarch*, bfd*, int*)’ at ../../binutils-gdb/gdb/linux-tdep.c:1878:27: /usr/include/bits/string_fortified.h:106:34: error: ‘char* __builtin_strncpy(char*, const char*, long unsigned int)’ specified bound 81 equals destination size [-Werror=stringop-truncation] This patch fixes the problem by using "sizeof - 1" in the call to strndup, as recommended in the GCC manual. This doesn't make a difference here because the next line, in all cases, sets the final element to '\0' anyway. gdb/ChangeLog 2020-03-20 Tom Tromey * ada-tasks.c (read_atcb): Use smaller length in strncpy call. * linux-tdep.c (linux_fill_prpsinfo): Use smaller length in strncpy call. Diff: --- gdb/ChangeLog | 6 ++++++ gdb/ada-tasks.c | 3 ++- gdb/linux-tdep.c | 4 ++-- 3 files changed, 10 insertions(+), 3 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index f1b007b1ba3..583ec9c81e3 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2020-03-20 Tom Tromey + + * ada-tasks.c (read_atcb): Use smaller length in strncpy call. + * linux-tdep.c (linux_fill_prpsinfo): Use smaller length in + strncpy call. + 2020-03-20 Tom Tromey * symmisc.c (maintenance_print_one_line_table): Use ui_out. diff --git a/gdb/ada-tasks.c b/gdb/ada-tasks.c index 0a81c3c6922..589d5e84e0a 100644 --- a/gdb/ada-tasks.c +++ b/gdb/ada-tasks.c @@ -679,7 +679,8 @@ read_atcb (CORE_ADDR task_id, struct ada_task_info *task_info) task_name = p + 2; /* Copy the task name. */ - strncpy (task_info->name, task_name, sizeof (task_info->name)); + strncpy (task_info->name, task_name, + sizeof (task_info->name) - 1); task_info->name[sizeof (task_info->name) - 1] = 0; } else diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c index b6374ce399c..e50946ce379 100644 --- a/gdb/linux-tdep.c +++ b/gdb/linux-tdep.c @@ -1729,7 +1729,7 @@ linux_fill_prpsinfo (struct elf_internal_linux_prpsinfo *p) /* Copying the program name. Only the basename matters. */ basename = lbasename (fname.get ()); - strncpy (p->pr_fname, basename, sizeof (p->pr_fname)); + strncpy (p->pr_fname, basename, sizeof (p->pr_fname) - 1); p->pr_fname[sizeof (p->pr_fname) - 1] = '\0'; infargs = get_inferior_args (); @@ -1739,7 +1739,7 @@ linux_fill_prpsinfo (struct elf_internal_linux_prpsinfo *p) if (infargs != NULL) psargs = psargs + " " + infargs; - strncpy (p->pr_psargs, psargs.c_str (), sizeof (p->pr_psargs)); + strncpy (p->pr_psargs, psargs.c_str (), sizeof (p->pr_psargs) - 1); p->pr_psargs[sizeof (p->pr_psargs) - 1] = '\0'; xsnprintf (filename, sizeof (filename), "/proc/%d/stat", (int) pid);