Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

signal: Properly deliver SIGILL from uprobes

Browse source 
[ Upstream commit 55a3235fc71bf34303e34a95eeee235b2d2a35dd ]

For userspace to tell the difference between a random signal and an
exception, the exception must include siginfo information.

Using SEND_SIG_FORCED for SIGILL is thus wrong, and it will result
in userspace seeing si_code == SI_USER (like a random signal) instead
of si_code == SI_KERNEL or a more specific si_code as all exceptions
deliver.

Therefore replace force_sig_info(SIGILL, SEND_SIG_FORCE, current)
with force_sig(SIG_ILL, current) which gets this right and is
shorter and easier to type.

Fixes: 014940bad8 ("uprobes/x86: Send SIGILL if arch_uprobe_post_xol() fails")
Fixes: 0b5256c7f1 ("uprobes: Send SIGILL if handle_trampoline() fails")
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Eric W. Biederman 2018-07-19 20:33:53 -05:00 • committed by Greg Kroah-Hartman
parent 3b5681d39f
commit 91c3a88054
1 changed files with 2 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
kernel/events/uprobes.c
View file

@ -1858,7 +1858,7 @@ static void handle_trampoline(struct pt_regs *regs)
sigill:
uprobe_warn(current, "handle uretprobe, sending SIGILL.");
force_sig_info(SIGILL, SEND_SIG_FORCED, current);
force_sig(SIGILL, current);
}
@ -1974,7 +1974,7 @@ static void handle_singlestep(struct uprobe_task *utask, struct pt_regs *regs)
if (unlikely(err)) {
uprobe_warn(current, "execute the probed insn, sending SIGILL.");
force_sig_info(SIGILL, SEND_SIG_FORCED, current);
force_sig(SIGILL, current);
}
}