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Re: [patch] Fix crash on /proc/PID/stat race
On Fri, 28 May 2010 00:25:40 +0200, Pedro Alves wrote:
> Yes, exactly. Thanks.
Checked-in:
http://sourceware.org/ml/gdb-cvs/2010-05/msg00243.html
> As long as a process hasn't been waited for, the /stat entry should exist,
> even if the process is zombie.
I agree but still finding such external dependency needlessly fragile.
> Anyway, if you want to put that one in, it's okay, but please don't
> lose the comment below:
>
> > - p = strchr (p, ')') + 2; /* skip ")" and a whitespace. */
> > + if (p != NULL)
> > + p = strchr (p, ')');
The part "and a whitespace." was removed as redundant (due to the following
strtok_r) while getting more complicated making it safe. In the spirit of GNU
Coding Style
"It is not necessary to duplicate in words the meaning of the
C argument declarations"
(while used in a different meaning at that point) I removed the remainder of
the comment
/* skip ")" */
for the block
if (p != NULL)
p = strchr (p, ')');
if (p != NULL)
p++;
as obvious; but I put it back now on your request.
> and I don't think the fopen race comment makes sense > as is anymore.
OK, removed that comment.
> Also, IWBN if gdbserver was fixed similarly, but I won't ask
> you to do that. :-)
Forgot/unaware, fixed the same way.
Checked-in.
Thanks,
Jan
http://sourceware.org/ml/gdb-cvs/2010-05/msg00244.html
--- src/gdb/ChangeLog 2010/05/28 18:00:41 1.11855
+++ src/gdb/ChangeLog 2010/05/28 18:23:13 1.11856
@@ -1,5 +1,10 @@
2010-05-28 Jan Kratochvil <jan.kratochvil@redhat.com>
+ * linux-nat.c (linux_nat_core_of_thread_1): Fix crash on invalid
+ CONTENT.
+
+2010-05-28 Jan Kratochvil <jan.kratochvil@redhat.com>
+
* linux-nat.c (linux_nat_wait_1): Do not call
linux_nat_core_of_thread_1 on TARGET_WAITKIND_EXITED or
TARGET_WAITKIND_SIGNALLED.
--- src/gdb/gdbserver/ChangeLog 2010/05/26 22:40:22 1.386
+++ src/gdb/gdbserver/ChangeLog 2010/05/28 18:23:15 1.387
@@ -1,3 +1,8 @@
+2010-05-28 Jan Kratochvil <jan.kratochvil@redhat.com>
+
+ * linux-low.c (linux_core_of_thread): Fix crash on invalid CONTENT.
+ New comment.
+
2010-05-26 Ozkan Sezer <sezeroz@gmail.com>
* gdbreplay.c (remote_open): Check error return from socket() call by
--- src/gdb/linux-nat.c 2010/05/28 18:00:46 1.169
+++ src/gdb/linux-nat.c 2010/05/28 18:23:15 1.170
@@ -5509,15 +5509,21 @@
make_cleanup (xfree, content);
p = strchr (content, '(');
- p = strchr (p, ')') + 2; /* skip ")" and a whitespace. */
+
+ /* Skip ")". */
+ if (p != NULL)
+ p = strchr (p, ')');
+ if (p != NULL)
+ p++;
/* If the first field after program name has index 0, then core number is
the field with index 36. There's no constant for that anywhere. */
- p = strtok_r (p, " ", &ts);
- for (i = 0; i != 36; ++i)
+ if (p != NULL)
+ p = strtok_r (p, " ", &ts);
+ for (i = 0; p != NULL && i != 36; ++i)
p = strtok_r (NULL, " ", &ts);
- if (sscanf (p, "%d", &core) == 0)
+ if (p == NULL || sscanf (p, "%d", &core) == 0)
core = -1;
do_cleanups (back_to);
--- src/gdb/gdbserver/linux-low.c 2010/05/03 04:02:20 1.148
+++ src/gdb/gdbserver/linux-low.c 2010/05/28 18:23:15 1.149
@@ -4346,13 +4346,21 @@
}
p = strchr (content, '(');
- p = strchr (p, ')') + 2; /* skip ")" and a whitespace. */
- p = strtok_r (p, " ", &ts);
- for (i = 0; i != 36; ++i)
+ /* Skip ")". */
+ if (p != NULL)
+ p = strchr (p, ')');
+ if (p != NULL)
+ p++;
+
+ /* If the first field after program name has index 0, then core number is
+ the field with index 36. There's no constant for that anywhere. */
+ if (p != NULL)
+ p = strtok_r (p, " ", &ts);
+ for (i = 0; p != NULL && i != 36; ++i)
p = strtok_r (NULL, " ", &ts);
- if (sscanf (p, "%d", &core) == 0)
+ if (p == NULL || sscanf (p, "%d", &core) == 0)
core = -1;
free (content);