lkml.org 
[lkml]   [2019]   [Feb]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.14 56/62] x86/a.out: Clear the dump structure initially
Date
4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Borislav Petkov <bp@suse.de>

commit 10970e1b4be9c74fce8ab6e3c34a7d718f063f2c upstream.

dump_thread32() in aout_core_dump() does not clear the user32 structure
allocated on the stack as the first thing on function entry.

As a result, the dump.u_comm, dump.u_ar0 and dump.signal which get
assigned before the clearing, get overwritten.

Rename that function to fill_dump() to make it clear what it does and
call it first thing.

This was caught while staring at a patch by Derek Robson
<robsonde@gmail.com>.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Derek Robson <robsonde@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Matz <matz@suse.de>
Cc: x86@kernel.org
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20190202005512.3144-1-robsonde@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/x86/ia32/ia32_aout.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/x86/ia32/ia32_aout.c
+++ b/arch/x86/ia32/ia32_aout.c
@@ -51,7 +51,7 @@ static unsigned long get_dr(int n)
/*
* fill in the user structure for a core dump..
*/
-static void dump_thread32(struct pt_regs *regs, struct user32 *dump)
+static void fill_dump(struct pt_regs *regs, struct user32 *dump)
{
u32 fs, gs;
memset(dump, 0, sizeof(*dump));
@@ -157,10 +157,12 @@ static int aout_core_dump(struct coredum
fs = get_fs();
set_fs(KERNEL_DS);
has_dumped = 1;
+
+ fill_dump(cprm->regs, &dump);
+
strncpy(dump.u_comm, current->comm, sizeof(current->comm));
dump.u_ar0 = offsetof(struct user32, regs);
dump.signal = cprm->siginfo->si_signo;
- dump_thread32(cprm->regs, &dump);

/*
* If the size of the dump file exceeds the rlimit, then see

\
 
 \ /
  Last update: 2019-02-18 14:57    [W:0.766 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site