From e0ddf8eac9f83c0bc5a3d39605d873ee0fe53421 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sat, 8 Jul 2023 07:00:25 +0200 Subject: linux-user: Fix fcntl() and fcntl64() to return O_LARGEFILE for 32-bit targets When running a 32-bit guest on a 64-bit host, fcntl[64](F_GETFL) should return with the TARGET_O_LARGEFILE flag set, because all 64-bit hosts support large files unconditionally. But on 64-bit hosts, O_LARGEFILE has the value 0, so the flag translation can't be done with the fcntl_flags_tbl[]. Instead add the TARGET_O_LARGEFILE flag afterwards. Note that for 64-bit guests the compiler will optimize away this code, since TARGET_O_LARGEFILE is zero. Signed-off-by: Helge Deller Reviewed-by: Richard Henderson --- linux-user/syscall.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 08162cc966..10f05b1e55 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -7132,6 +7132,10 @@ static abi_long do_fcntl(int fd, int cmd, abi_ulong arg) ret = get_errno(safe_fcntl(fd, host_cmd, arg)); if (ret >= 0) { ret = host_to_target_bitmask(ret, fcntl_flags_tbl); + /* tell 32-bit guests it uses largefile on 64-bit hosts: */ + if (O_LARGEFILE == 0 && HOST_LONG_BITS == 64) { + ret |= TARGET_O_LARGEFILE; + } } break; -- cgit v1.2.3 From dca4c8384d68bbf5d67f50a5446865d92d61f032 Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sat, 8 Jul 2023 07:24:00 +0200 Subject: linux-user: Fix accept4(SOCK_NONBLOCK) syscall The Linux accept4() syscall allows two flags only: SOCK_NONBLOCK and SOCK_CLOEXEC, and returns -EINVAL if any other bits have been set. Change the qemu implementation accordingly, which means we can not use the fcntl_flags_tbl[] translation table which allows too many other values. Beside the correction in behaviour, this actually fixes the accept4() emulation for hppa, mips and alpha targets for which SOCK_NONBLOCK is different than TARGET_SOCK_NONBLOCK (aka O_NONBLOCK). The fix can be verified with the testcase of the debian lwt package, which hangs forever in a read() syscall without this patch. Signed-off-by: Helge Deller Reviewed-by: Richard Henderson --- linux-user/syscall.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 10f05b1e55..9b9e3bd5e3 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -3440,7 +3440,17 @@ static abi_long do_accept4(int fd, abi_ulong target_addr, abi_long ret; int host_flags; - host_flags = target_to_host_bitmask(flags, fcntl_flags_tbl); + if (flags & ~(TARGET_SOCK_CLOEXEC | TARGET_SOCK_NONBLOCK)) { + return -TARGET_EINVAL; + } + + host_flags = 0; + if (flags & TARGET_SOCK_NONBLOCK) { + host_flags |= SOCK_NONBLOCK; + } + if (flags & TARGET_SOCK_CLOEXEC) { + host_flags |= SOCK_CLOEXEC; + } if (target_addr == 0) { return get_errno(safe_accept4(fd, NULL, NULL, host_flags)); -- cgit v1.2.3 From 036cf169a3484eeca5e17cfbee1f6988043ddd0e Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Sun, 12 Mar 2023 23:17:13 +0100 Subject: linux-user: Improve strace output of pread64() and pwrite64() Make the strace look nicer for those two syscalls. Signed-off-by: Helge Deller Reviewed-by: Richard Henderson --- linux-user/strace.c | 19 +++++++++++++++++++ linux-user/strace.list | 4 ++-- 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/linux-user/strace.c b/linux-user/strace.c index aad2b62ca4..669200c4a4 100644 --- a/linux-user/strace.c +++ b/linux-user/strace.c @@ -3999,6 +3999,25 @@ print_tgkill(CPUArchState *cpu_env, const struct syscallname *name, } #endif +#if defined(TARGET_NR_pread64) || defined(TARGET_NR_pwrite64) +static void +print_pread64(CPUArchState *cpu_env, const struct syscallname *name, + abi_long arg0, abi_long arg1, abi_long arg2, + abi_long arg3, abi_long arg4, abi_long arg5) +{ + if (regpairs_aligned(cpu_env, TARGET_NR_pread64)) { + arg3 = arg4; + arg4 = arg5; + } + print_syscall_prologue(name); + print_raw_param("%d", arg0, 0); + print_pointer(arg1, 0); + print_raw_param("%d", arg2, 0); + print_raw_param("%" PRIu64, target_offset64(arg3, arg4), 1); + print_syscall_epilogue(name); +} +#endif + #ifdef TARGET_NR_statx static void print_statx(CPUArchState *cpu_env, const struct syscallname *name, diff --git a/linux-user/strace.list b/linux-user/strace.list index c7808ea118..6655d4f26d 100644 --- a/linux-user/strace.list +++ b/linux-user/strace.list @@ -1068,7 +1068,7 @@ { TARGET_NR_prctl, "prctl" , NULL, NULL, NULL }, #endif #ifdef TARGET_NR_pread64 -{ TARGET_NR_pread64, "pread64" , NULL, NULL, NULL }, +{ TARGET_NR_pread64, "pread64" , NULL, print_pread64, NULL }, #endif #ifdef TARGET_NR_preadv { TARGET_NR_preadv, "preadv" , NULL, NULL, NULL }, @@ -1099,7 +1099,7 @@ { TARGET_NR_putpmsg, "putpmsg" , NULL, NULL, NULL }, #endif #ifdef TARGET_NR_pwrite64 -{ TARGET_NR_pwrite64, "pwrite64" , NULL, NULL, NULL }, +{ TARGET_NR_pwrite64, "pwrite64" , NULL, print_pread64, NULL }, #endif #ifdef TARGET_NR_pwritev { TARGET_NR_pwritev, "pwritev" , NULL, NULL, NULL }, -- cgit v1.2.3