Commit-ID: 10970e1b4be9c74fce8ab6e3c34a7d718f063f2c Gitweb: https://git.kernel.org/tip/10970e1b4be9c74fce8ab6e3c34a7d718f063f2c Author: Borislav Petkov bp@suse.de AuthorDate: Tue, 12 Feb 2019 14:28:03 +0100 Committer: Borislav Petkov bp@suse.de CommitDate: Wed, 13 Feb 2019 12:10:51 +0100

x86/a.out: Clear the dump structure initially

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

diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c index f65b78d32f5e..7dbbe9ffda17 100644 --- 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 coredump_params *cprm) 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