From b813377f6c746118a9d2625e6b29ffeec4233663 Mon Sep 17 00:00:00 2001 From: Khem Raj Date: Fri, 3 Feb 2012 20:06:55 -0800 Subject: [PATCH 3/4] lstat/stat/fstat: Use 64bit version of syscall if available This is needed for stat'ing loop devices > 255 since otherwise kernel returns EOVERFLOW becasue it needs st_rdev/st_dev to be larger than 16bits but in kernel it uses __old_kernel_stat for stat syscall which has st_rdev/st_dev as unsigned short Add a testcase Signed-off-by: Khem Raj Signed-off-by: Bernhard Reutner-Fischer --- libc/sysdeps/linux/common/fstat.c | 18 ++++++++++++++---- libc/sysdeps/linux/common/lstat.c | 19 ++++++++++++++----- libc/sysdeps/linux/common/stat.c | 18 ++++++++++++++---- test/stat/stat-loop256.c | 32 ++++++++++++++++++++++++++++++++ 4 files changed, 74 insertions(+), 13 deletions(-) create mode 100644 test/stat/stat-loop256.c diff --git a/libc/sysdeps/linux/common/fstat.c b/libc/sysdeps/linux/common/fstat.c index acc639b..4726a68 100644 --- a/libc/sysdeps/linux/common/fstat.c +++ b/libc/sysdeps/linux/common/fstat.c @@ -12,18 +12,28 @@ #include #include "xstatconv.h" -#define __NR___syscall_fstat __NR_fstat -static __inline__ _syscall2(int, __syscall_fstat, int, fd, struct kernel_stat *, buf) - int fstat(int fd, struct stat *buf) { int result; +#ifdef __NR_fstat64 + /* normal stat call has limited values for various stat elements + * e.g. uid device major/minor etc. + * so we use 64 variant if available + * in order to get newer versions of stat elements + */ + struct kernel_stat64 kbuf; + result = INLINE_SYSCALL(fstat64, 2, fd, &kbuf); + if (result == 0) { + __xstat32_conv(&kbuf, buf); + } +#else struct kernel_stat kbuf; - result = __syscall_fstat(fd, &kbuf); + result = INLINE_SYSCALL(fstat, 2, fd, &kbuf); if (result == 0) { __xstat_conv(&kbuf, buf); } +#endif return result; } libc_hidden_def(fstat) diff --git a/libc/sysdeps/linux/common/lstat.c b/libc/sysdeps/linux/common/lstat.c index aa77447..db72d1f 100644 --- a/libc/sysdeps/linux/common/lstat.c +++ b/libc/sysdeps/linux/common/lstat.c @@ -12,19 +12,28 @@ #include #include "xstatconv.h" -#define __NR___syscall_lstat __NR_lstat -static __inline__ _syscall2(int, __syscall_lstat, - const char *, file_name, struct kernel_stat *, buf) - int lstat(const char *file_name, struct stat *buf) { int result; +#ifdef __NR_lstat64 + /* normal stat call has limited values for various stat elements + * e.g. uid device major/minor etc. + * so we use 64 variant if available + * in order to get newer versions of stat elements + */ + struct kernel_stat64 kbuf; + result = INLINE_SYSCALL(lstat64, 2, file_name, &kbuf); + if (result == 0) { + __xstat32_conv(&kbuf, buf); + } +#else struct kernel_stat kbuf; - result = __syscall_lstat(file_name, &kbuf); + result = INLINE_SYSCALL(lstat, 2, file_name, &kbuf); if (result == 0) { __xstat_conv(&kbuf, buf); } +#endif return result; } libc_hidden_def(lstat) diff --git a/libc/sysdeps/linux/common/stat.c b/libc/sysdeps/linux/common/stat.c index a6ab291..829f35a 100644 --- a/libc/sysdeps/linux/common/stat.c +++ b/libc/sysdeps/linux/common/stat.c @@ -12,20 +12,30 @@ #include #include "xstatconv.h" -#define __NR___syscall_stat __NR_stat #undef stat -static __inline__ _syscall2(int, __syscall_stat, - const char *, file_name, struct kernel_stat *, buf) int stat(const char *file_name, struct stat *buf) { int result; +#ifdef __NR_stat64 + /* normal stat call has limited values for various stat elements + * e.g. uid device major/minor etc. + * so we use 64 variant if available + * in order to get newer versions of stat elements + */ + struct kernel_stat64 kbuf; + result = INLINE_SYSCALL(stat64, 2, file_name, &kbuf); + if (result == 0) { + __xstat32_conv(&kbuf, buf); + } +#else struct kernel_stat kbuf; - result = __syscall_stat(file_name, &kbuf); + result = INLINE_SYSCALL(stat, 2, file_name, &kbuf); if (result == 0) { __xstat_conv(&kbuf, buf); } +#endif return result; } libc_hidden_def(stat) diff --git a/test/stat/stat-loop256.c b/test/stat/stat-loop256.c new file mode 100644 index 0000000..14284c1 --- /dev/null +++ b/test/stat/stat-loop256.c @@ -0,0 +1,32 @@ +#include +#include +#include +#include +int main() +{ + struct stat statbuf; + int ret = 0; + char* loop255 = "/dev/loop255"; + char* loop256 = "/dev/loop256"; + mode_t mode = 0660; + mknod(loop255, mode, 0x7ff); + mknod(loop256, mode, 0x100700); + ret = stat(loop255, &statbuf); + if(ret < 0) { + printf("stat: Cant stat %s\n",loop255); + unlink(loop255); + exit(1); + } + ret = stat(loop256, &statbuf); + if(ret < 0) { + printf("stat: Cant stat %s\n",loop256); + unlink(loop255); + unlink(loop256); + exit(1); + } + + unlink(loop255); + unlink(loop256); + exit(0); +} + -- 1.7.8.3