/* * Seccomp BPF example using a macro-based generator. * * Copyright (c) 2012 The Chromium OS Authors * Author: Will Drewry * * The code may be used by anyone for any purpose, * and can serve as a starting point for developing * applications using prctl(PR_ATTACH_SECCOMP_FILTER). */ #include #include #include #include #include #include #include #include "bpf-helper.h" #ifndef PR_SET_NO_NEW_PRIVS #define PR_SET_NO_NEW_PRIVS 38 #endif int main(int argc, char **argv) { struct bpf_labels l = { .count = 0, }; static const char msg1[] = "Please type something: "; static const char msg2[] = "You typed: "; char buf[256]; struct sock_filter filter[] = { /* TODO: LOAD_SYSCALL_NR(arch) and enforce an arch */ LOAD_SYSCALL_NR, SYSCALL(__NR_exit, ALLOW), SYSCALL(__NR_exit_group, ALLOW), SYSCALL(__NR_write, JUMP(&l, write_fd)), SYSCALL(__NR_read, JUMP(&l, read)), DENY, /* Don't passthrough into a label */ LABEL(&l, read), ARG(0), JNE(STDIN_FILENO, DENY), ARG(1), JNE((unsigned long)buf, DENY), ARG(2), JGE(sizeof(buf), DENY), ALLOW, LABEL(&l, write_fd), ARG(0), JEQ(STDOUT_FILENO, JUMP(&l, write_buf)), JEQ(STDERR_FILENO, JUMP(&l, write_buf)), DENY, LABEL(&l, write_buf), ARG(1), JEQ((unsigned long)msg1, JUMP(&l, msg1_len)), JEQ((unsigned long)msg2, JUMP(&l, msg2_len)), JEQ((unsigned long)buf, JUMP(&l, buf_len)), DENY, LABEL(&l, msg1_len), ARG(2), JLT(sizeof(msg1), ALLOW), DENY, LABEL(&l, msg2_len), ARG(2), JLT(sizeof(msg2), ALLOW), DENY, LABEL(&l, buf_len), ARG(2), JLT(sizeof(buf), ALLOW), DENY, }; struct sock_fprog prog = { .filter = filter, .len = (unsigned short)(sizeof(filter)/sizeof(filter[0])), }; ssize_t bytes; bpf_resolve_jumps(&l, filter, sizeof(filter)/sizeof(*filter)); if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { perror("prctl(NO_NEW_PRIVS)"); return 1; } if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog)) { perror("prctl(SECCOMP)"); return 1; } syscall(__NR_write, STDOUT_FILENO, msg1, strlen(msg1)); bytes = syscall(__NR_read, STDIN_FILENO, buf, sizeof(buf)-1); bytes = (bytes > 0 ? bytes : 0); syscall(__NR_write, STDERR_FILENO, msg2, strlen(msg2)); syscall(__NR_write, STDERR_FILENO, buf, bytes); /* Now get killed */ syscall(__NR_write, STDERR_FILENO, msg2, strlen(msg2)+2); return 0; } e-remove'/>
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authorThomas Gleixner <tglx@linutronix.de>2017-01-31 09:37:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100
commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /drivers/usb/phy/phy-omap-otg.c
parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'drivers/usb/phy/phy-omap-otg.c')