| Message ID | 1463075272-9933-3-git-send-email-peter.maydell@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Le 12/05/2016 à 19:47, Peter Maydell a écrit : > The function do_openat() is not consistent about whether it is > returning a host errno or a guest errno in case of failure. > Standardise on returning -1 with errno set (ie caller has > to call get_errno()). > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > Reported-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk> Reviewed-by: Laurent Vivier <laurent@vivier.eu> > --- > Timothy's patchset for fixing signal races had a patch which also > addressed this bug. However I preferred to take the opposite tack > and have the callers do get_errno() rather than the callee, because > it means changes in fewer places and it's generally more natural > for the 'fill' functions that do_openat() calls. > --- > linux-user/syscall.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/linux-user/syscall.c b/linux-user/syscall.c > index 5246f36..f4c2e19 100644 > --- a/linux-user/syscall.c > +++ b/linux-user/syscall.c > @@ -5559,7 +5559,9 @@ static int open_self_cmdline(void *cpu_env, int fd) > > nb_read = read(fd_orig, buf, sizeof(buf)); > if (nb_read < 0) { > + int e = errno; > fd_orig = close(fd_orig); > + errno = e; > return -1; > } else if (nb_read == 0) { > break; > @@ -5579,7 +5581,9 @@ static int open_self_cmdline(void *cpu_env, int fd) > > if (word_skipped) { > if (write(fd, cp_buf, nb_read) != nb_read) { > + int e = errno; > close(fd_orig); > + errno = e; > return -1; > } > } > @@ -5599,7 +5603,7 @@ static int open_self_maps(void *cpu_env, int fd) > > fp = fopen("/proc/self/maps", "r"); > if (fp == NULL) { > - return -EACCES; > + return -1; > } > > while ((read = getline(&line, &len, fp)) != -1) { > @@ -5743,7 +5747,7 @@ static int open_net_route(void *cpu_env, int fd) > > fp = fopen("/proc/net/route", "r"); > if (fp == NULL) { > - return -EACCES; > + return -1; > } > > /* read header */ > @@ -5793,7 +5797,7 @@ static int do_openat(void *cpu_env, int dirfd, const char *pathname, int flags, > > if (is_proc_myself(pathname, "exe")) { > int execfd = qemu_getauxval(AT_EXECFD); > - return execfd ? execfd : get_errno(sys_openat(dirfd, exec_path, flags, mode)); > + return execfd ? execfd : sys_openat(dirfd, exec_path, flags, mode); > } > > for (fake_open = fakes; fake_open->filename; fake_open++) { > @@ -5819,7 +5823,9 @@ static int do_openat(void *cpu_env, int dirfd, const char *pathname, int flags, > unlink(filename); > > if ((r = fake_open->fill(cpu_env, fd))) { > + int e = errno; > close(fd); > + errno = e; > return r; > } > lseek(fd, 0, SEEK_SET); > @@ -5827,7 +5833,7 @@ static int do_openat(void *cpu_env, int dirfd, const char *pathname, int flags, > return fd; > } > > - return get_errno(sys_openat(dirfd, path(pathname), flags, mode)); > + return sys_openat(dirfd, path(pathname), flags, mode); > } > > #define TIMER_MAGIC 0x0caf0000 >
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 5246f36..f4c2e19 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -5559,7 +5559,9 @@ static int open_self_cmdline(void *cpu_env, int fd) nb_read = read(fd_orig, buf, sizeof(buf)); if (nb_read < 0) { + int e = errno; fd_orig = close(fd_orig); + errno = e; return -1; } else if (nb_read == 0) { break; @@ -5579,7 +5581,9 @@ static int open_self_cmdline(void *cpu_env, int fd) if (word_skipped) { if (write(fd, cp_buf, nb_read) != nb_read) { + int e = errno; close(fd_orig); + errno = e; return -1; } } @@ -5599,7 +5603,7 @@ static int open_self_maps(void *cpu_env, int fd) fp = fopen("/proc/self/maps", "r"); if (fp == NULL) { - return -EACCES; + return -1; } while ((read = getline(&line, &len, fp)) != -1) { @@ -5743,7 +5747,7 @@ static int open_net_route(void *cpu_env, int fd) fp = fopen("/proc/net/route", "r"); if (fp == NULL) { - return -EACCES; + return -1; } /* read header */ @@ -5793,7 +5797,7 @@ static int do_openat(void *cpu_env, int dirfd, const char *pathname, int flags, if (is_proc_myself(pathname, "exe")) { int execfd = qemu_getauxval(AT_EXECFD); - return execfd ? execfd : get_errno(sys_openat(dirfd, exec_path, flags, mode)); + return execfd ? execfd : sys_openat(dirfd, exec_path, flags, mode); } for (fake_open = fakes; fake_open->filename; fake_open++) { @@ -5819,7 +5823,9 @@ static int do_openat(void *cpu_env, int dirfd, const char *pathname, int flags, unlink(filename); if ((r = fake_open->fill(cpu_env, fd))) { + int e = errno; close(fd); + errno = e; return r; } lseek(fd, 0, SEEK_SET); @@ -5827,7 +5833,7 @@ static int do_openat(void *cpu_env, int dirfd, const char *pathname, int flags, return fd; } - return get_errno(sys_openat(dirfd, path(pathname), flags, mode)); + return sys_openat(dirfd, path(pathname), flags, mode); } #define TIMER_MAGIC 0x0caf0000
The function do_openat() is not consistent about whether it is returning a host errno or a guest errno in case of failure. Standardise on returning -1 with errno set (ie caller has to call get_errno()). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reported-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk> --- Timothy's patchset for fixing signal races had a patch which also addressed this bug. However I preferred to take the opposite tack and have the callers do get_errno() rather than the callee, because it means changes in fewer places and it's generally more natural for the 'fill' functions that do_openat() calls. --- linux-user/syscall.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)