* 2.02-beta3 remove attempt to free stack space and initialize variable before possible use
@ 2016-03-14 14:37 Aaron Luft
2016-03-14 17:35 ` Andrei Borzenkov
0 siblings, 1 reply; 4+ messages in thread
From: Aaron Luft @ 2016-03-14 14:37 UTC (permalink / raw)
To: grub-devel@gnu.org
Please consider these improvements to 2.02-beta3.
1) Remove the variable "oldname" which is attempting to free stack space.
2) Initialize the value of mdnobj to silence the compiler warning
In function 'grub_free',
inlined from 'grub_iso9660_iterate_dir' at grub-core/fs/iso9660.c:764:15:
grub-core/kern/emu/mm.c:53:3: error: attempt to free a non-heap object 'name' [-Werror=free-nonheap-object]
free (ptr);
^
lto1: all warnings being treated as errors
lto-wrapper: fatal error: x86_64-linux-gnu-gcc-5.3.0 returned 1 exit status
grub-core/fs/zfs/zfsinfo.c: In function 'grub_cmd_zfs_bootfs':
grub-core/fs/zfs/zfsinfo.c:401:10: error: 'mdnobj' may be used uninitialized in this function [-Werror=maybe-uninitialized]
bootfs = grub_xasprintf ("zfs-bootfs=%s/%llu%s%s%s%s%s%s",
^
grub-core/fs/zfs/zfsinfo.c:355:17: note: 'mdnobj' was declared here
grub_uint64_t mdnobj;
^
lto1: all warnings being treated as errors
diff -Naur grub-2.02-beta3.orig/grub-core/fs/iso9660.c grub-2.02-beta3/grub-core/fs/iso9660.c
--- grub-2.02-beta3.orig/grub-core/fs/iso9660.c 2016-02-28 02:07:41.000000000 +0000
+++ grub-2.02-beta3/grub-core/fs/iso9660.c 2016-03-12 01:17:26.581112809 +0000
@@ -750,19 +750,15 @@
if (dir->data->joliet && !ctx.filename)
{
- char *oldname, *semicolon;
+ char *semicolon;
- oldname = name;
ctx.filename = grub_iso9660_convert_string
- ((grub_uint8_t *) oldname, dirent.namelen >> 1);
+ ((grub_uint8_t *) name, dirent.namelen >> 1);
semicolon = grub_strrchr (ctx.filename, ';');
if (semicolon)
*semicolon = '\0';
- if (ctx.filename_alloc)
- grub_free (oldname);
-
ctx.filename_alloc = 1;
}
diff -Naur grub-2.02-beta3.orig/grub-core/fs/zfs/zfsinfo.c grub-2.02-beta3/grub-core/fs/zfs/zfsinfo.c
--- grub-2.02-beta3.orig/grub-core/fs/zfs/zfsinfo.c 2016-02-28 02:07:41.000000000 +0000
+++ grub-2.02-beta3/grub-core/fs/zfs/zfsinfo.c 2016-03-12 01:18:00.504961950 +0000
@@ -352,7 +352,7 @@
char *fsname;
char *bootfs;
char *poolname;
- grub_uint64_t mdnobj;
+ grub_uint64_t mdnobj = 0;
if (argc < 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: 2.02-beta3 remove attempt to free stack space and initialize variable before possible use 2016-03-14 14:37 2.02-beta3 remove attempt to free stack space and initialize variable before possible use Aaron Luft @ 2016-03-14 17:35 ` Andrei Borzenkov 2016-03-14 21:21 ` Aaron Luft 0 siblings, 1 reply; 4+ messages in thread From: Andrei Borzenkov @ 2016-03-14 17:35 UTC (permalink / raw) To: The development of GNU GRUB, aluft 14.03.2016 17:37, Aaron Luft пишет: > Please consider these improvements to 2.02-beta3. > 1) Remove the variable "oldname" which is attempting to free stack space. > 2) Initialize the value of mdnobj to silence the compiler warning > > In function 'grub_free', > inlined from 'grub_iso9660_iterate_dir' at grub-core/fs/iso9660.c:764:15: > grub-core/kern/emu/mm.c:53:3: error: attempt to free a non-heap object 'name' [-Werror=free-nonheap-object] > free (ptr); > ^ > lto1: all warnings being treated as errors > lto-wrapper: fatal error: x86_64-linux-gnu-gcc-5.3.0 returned 1 exit status > > grub-core/fs/zfs/zfsinfo.c: In function 'grub_cmd_zfs_bootfs': > grub-core/fs/zfs/zfsinfo.c:401:10: error: 'mdnobj' may be used uninitialized in this function [-Werror=maybe-uninitialized] > bootfs = grub_xasprintf ("zfs-bootfs=%s/%llu%s%s%s%s%s%s", > ^ > grub-core/fs/zfs/zfsinfo.c:355:17: note: 'mdnobj' was declared here > grub_uint64_t mdnobj; > ^ > lto1: all warnings being treated as errors > I cannot apply them due to whitespace changes. > > > diff -Naur grub-2.02-beta3.orig/grub-core/fs/iso9660.c grub-2.02-beta3/grub-core/fs/iso9660.c > --- grub-2.02-beta3.orig/grub-core/fs/iso9660.c 2016-02-28 02:07:41.000000000 +0000 > +++ grub-2.02-beta3/grub-core/fs/iso9660.c 2016-03-12 01:17:26.581112809 +0000 > @@ -750,19 +750,15 @@ > > if (dir->data->joliet && !ctx.filename) > { > - char *oldname, *semicolon; > + char *semicolon; > > - oldname = name; > ctx.filename = grub_iso9660_convert_string > - ((grub_uint8_t *) oldname, dirent.namelen >> 1); > + ((grub_uint8_t *) name, dirent.namelen >> 1); > > semicolon = grub_strrchr (ctx.filename, ';'); > if (semicolon) > *semicolon = '\0'; > > - if (ctx.filename_alloc) > - grub_free (oldname); > - > ctx.filename_alloc = 1; > } > Yes, this is one correct. Please resend as attached patch generated by "git format-patch" with suitable commit message. Do not expand tabs when editing. > diff -Naur grub-2.02-beta3.orig/grub-core/fs/zfs/zfsinfo.c grub-2.02-beta3/grub-core/fs/zfs/zfsinfo.c > --- grub-2.02-beta3.orig/grub-core/fs/zfs/zfsinfo.c 2016-02-28 02:07:41.000000000 +0000 > +++ grub-2.02-beta3/grub-core/fs/zfs/zfsinfo.c 2016-03-12 01:18:00.504961950 +0000 > @@ -352,7 +352,7 @@ > char *fsname; > char *bootfs; > char *poolname; > - grub_uint64_t mdnobj; > + grub_uint64_t mdnobj = 0; > > if (argc < 1) > return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected")); > Well ... it cannot really reach code where mdnobj is used if grub_zfs_getmdnobj() fails but static analyzer may not know it. How do you compile it? I cannot reproduce it using gcc 5.3.1 nor did it fail previously. Do you use non-standard compiler flags? ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: 2.02-beta3 remove attempt to free stack space and initialize variable before possible use 2016-03-14 17:35 ` Andrei Borzenkov @ 2016-03-14 21:21 ` Aaron Luft 2016-03-15 19:18 ` Andrei Borzenkov 0 siblings, 1 reply; 4+ messages in thread From: Aaron Luft @ 2016-03-14 21:21 UTC (permalink / raw) To: Andrei Borzenkov; +Cc: grub-devel@gnu.org [-- Attachment #1: Type: text/plain, Size: 705 bytes --] > On Mar 14, 2016, at 1:35 PM, Andrei Borzenkov <arvidjaar@gmail.com> wrote: > Yes, this is one correct. Please resend as attached patch generated by > "git format-patch" with suitable commit message. Do not expand tabs when > editing. > Ok, attaching the patch to this mail. > > Well ... it cannot really reach code where mdnobj is used if > grub_zfs_getmdnobj() fails but static analyzer may not know it. > > How do you compile it? I cannot reproduce it using gcc 5.3.1 nor did it > fail previously. Do you use non-standard compiler flags? Yes, non-standard command line. I found an extra -Wall that the standard build doesn't have. Appreciate your comments and time, Aaron [-- Attachment #2: grub-dont-free-stack-plus-one.patch --] [-- Type: application/octet-stream, Size: 1943 bytes --] From ff7dc2550f289f0ead3e4ee6a74003be7c98152f Mon Sep 17 00:00:00 2001 From: Aaron Luft <aluft@lifesize.com> Date: Mon, 14 Mar 2016 16:48:33 -0400 Subject: [PATCH 1/2] Remove the variable oldname which is attempting to free stack space. --- grub-core/fs/iso9660.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/grub-core/fs/iso9660.c b/grub-core/fs/iso9660.c index 67a67cf..c9c8374 100644 --- a/grub-core/fs/iso9660.c +++ b/grub-core/fs/iso9660.c @@ -750,19 +750,15 @@ grub_iso9660_iterate_dir (grub_fshelp_node_t dir, if (dir->data->joliet && !ctx.filename) { - char *oldname, *semicolon; + char *semicolon; - oldname = name; ctx.filename = grub_iso9660_convert_string - ((grub_uint8_t *) oldname, dirent.namelen >> 1); + ((grub_uint8_t *) name, dirent.namelen >> 1); semicolon = grub_strrchr (ctx.filename, ';'); if (semicolon) *semicolon = '\0'; - if (ctx.filename_alloc) - grub_free (oldname); - ctx.filename_alloc = 1; } -- 2.5.0 From c50f4167c59adefd30a6179fc967fecf33c7a895 Mon Sep 17 00:00:00 2001 From: Aaron Luft <aluft@lifesize.com> Date: Mon, 14 Mar 2016 16:48:56 -0400 Subject: [PATCH 2/2] Initialize the value of mdnobj to silence the compiler warning --- grub-core/fs/zfs/zfsinfo.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/grub-core/fs/zfs/zfsinfo.c b/grub-core/fs/zfs/zfsinfo.c index c8a28ac..926f966 100644 --- a/grub-core/fs/zfs/zfsinfo.c +++ b/grub-core/fs/zfs/zfsinfo.c @@ -352,7 +352,7 @@ grub_cmd_zfs_bootfs (grub_command_t cmd __attribute__ ((unused)), int argc, char *fsname; char *bootfs; char *poolname; - grub_uint64_t mdnobj; + grub_uint64_t mdnobj = 0; if (argc < 1) return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected")); -- 2.5.0 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: 2.02-beta3 remove attempt to free stack space and initialize variable before possible use 2016-03-14 21:21 ` Aaron Luft @ 2016-03-15 19:18 ` Andrei Borzenkov 0 siblings, 0 replies; 4+ messages in thread From: Andrei Borzenkov @ 2016-03-15 19:18 UTC (permalink / raw) To: Aaron Luft; +Cc: grub-devel@gnu.org 15.03.2016 00:21, Aaron Luft пишет: > >> On Mar 14, 2016, at 1:35 PM, Andrei Borzenkov <arvidjaar@gmail.com> wrote: >> Yes, this is one correct. Please resend as attached patch generated by >> "git format-patch" with suitable commit message. Do not expand tabs when >> editing. >> > Ok, attaching the patch to this mail. > I committed the iso9660 patch adding commit message with some explanation. >> >> Well ... it cannot really reach code where mdnobj is used if >> grub_zfs_getmdnobj() fails but static analyzer may not know it. >> >> How do you compile it? I cannot reproduce it using gcc 5.3.1 nor did it >> fail previously. Do you use non-standard compiler flags? > > Yes, non-standard command line. > I found an extra -Wall that the standard build doesn't have. > We use -Wall always. The problem is apparently caused by using LTO. Could you upload somewhere full log of configure && make with this error? ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-03-15 19:18 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2016-03-14 14:37 2.02-beta3 remove attempt to free stack space and initialize variable before possible use Aaron Luft 2016-03-14 17:35 ` Andrei Borzenkov 2016-03-14 21:21 ` Aaron Luft 2016-03-15 19:18 ` Andrei Borzenkov
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