From 031acdcfb566ba18ffb57d51abf357a5e350424b Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 10 Oct 2024 16:14:12 +0200 Subject: um: restore process name After the execve() to disable ASLR, comm is now "exe", which is a bit confusing. Use readlink() to get this to the right name again. Disable stack frame size warnings on main.o since it's part of the initial userspace and can use larger stack. Fixes: 68b9883cc16e ("um: Discover host_task_size from envp") Link: https://patch.msgid.link/20241010161411.c576e2aeb3e5.I244d4f34b8a8555ee5bec0e1cf5027bce4cc491b@changeid Signed-off-by: Johannes Berg --- arch/um/os-Linux/Makefile | 2 ++ arch/um/os-Linux/main.c | 14 ++++++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-) (limited to 'arch/um') diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile index 544e0b344c75..049dfa5bc9c6 100644 --- a/arch/um/os-Linux/Makefile +++ b/arch/um/os-Linux/Makefile @@ -12,6 +12,8 @@ obj-y = execvp.o file.o helper.o irq.o main.o mem.o process.o \ CFLAGS_signal.o += -Wframe-larger-than=4096 +CFLAGS_main.o += -Wno-frame-larger-than + obj-$(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA) += elf_aux.o USER_OBJS := $(user-objs-y) elf_aux.o execvp.o file.o helper.o irq.o \ diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c index 8a52c49c5361..5e0cba5aee93 100644 --- a/arch/um/os-Linux/main.c +++ b/arch/um/os-Linux/main.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -112,8 +113,17 @@ int __init main(int argc, char **argv, char **envp) /* Disable randomization and re-exec if it was changed successfully */ ret = personality(PER_LINUX | ADDR_NO_RANDOMIZE); if (ret >= 0 && (ret & (PER_LINUX | ADDR_NO_RANDOMIZE)) != - (PER_LINUX | ADDR_NO_RANDOMIZE)) - execve("/proc/self/exe", argv, envp); + (PER_LINUX | ADDR_NO_RANDOMIZE)) { + char buf[PATH_MAX] = {}; + ssize_t ret; + + ret = readlink("/proc/self/exe", buf, sizeof(buf)); + if (ret < 0 || ret >= sizeof(buf)) { + perror("readlink failure"); + exit(1); + } + execve(buf, argv, envp); + } set_stklim(); -- cgit v1.2.3