diff --git a/libmount-improve-mountinfo-reliability.patch b/libmount-improve-mountinfo-reliability.patch new file mode 100644 index 0000000..9366c94 --- /dev/null +++ b/libmount-improve-mountinfo-reliability.patch @@ -0,0 +1,383 @@ +From 32fe4f1dd8fbc104bd848e24de613122947f095a Mon Sep 17 00:00:00 2001 +From: Karel Zak +Date: Wed, 28 Aug 2019 15:47:16 +0200 +Subject: [PATCH] libmount: improve mountinfo reliability +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +The standard way how we read mount table is not reliable because +during the read() syscalls the table may be modified by some another +process. The changes in the table is possible to detect by poll() +event, and in this case it seems better to lseek to the begin of the file +and read it again. It's expensive, but better than races... + +This patch does not modify mountinfo parser, but it reads all file to +memory (by read()+poll()) and than it creates memory stream +from the buffer and use it rather than a regular file stream. + +It means the parser is still possible to use for normal files +(e.g. fstab) as well as for mountinfo and it's also portable to +systems where for some reason is no fmemopen(). + +Addresses: https://github.com/systemd/systemd/issues/10872 +Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1751447 +Upstream: http://github.com/karelzak/util-linux/commit/e4925f591c1bfb83719418b56b952830d15b77eb +Upstream: http://github.com/karelzak/util-linux/commit/ee551c909f95437fd9fcd162f398c069d0ce9720 +Reported-by: Zbigniew Jędrzejewski-Szmek +Signed-off-by: Karel Zak +--- +diff -up util-linux-2.34/configure.ac.kzak util-linux-2.34/configure.ac +--- util-linux-2.34/configure.ac.kzak 2019-06-14 12:34:02.892209368 +0200 ++++ util-linux-2.34/configure.ac 2019-09-13 09:19:54.155419473 +0200 +@@ -466,6 +466,7 @@ AC_CHECK_FUNCS([ \ + err \ + errx \ + explicit_bzero \ ++ fmemopen \ + fsync \ + utimensat \ + getdomainname \ +diff -up util-linux-2.34/libmount/src/mountP.h.kzak util-linux-2.34/libmount/src/mountP.h +--- util-linux-2.34/libmount/src/mountP.h.kzak 2019-05-09 14:15:40.637552762 +0200 ++++ util-linux-2.34/libmount/src/mountP.h 2019-09-13 09:19:54.155419473 +0200 +@@ -97,6 +97,7 @@ extern int mnt_valid_tagname(const char + extern int append_string(char **a, const char *b); + + extern const char *mnt_statfs_get_fstype(struct statfs *vfs); ++extern int is_procfs_fd(int fd); + extern int is_file_empty(const char *name); + + extern int mnt_is_readonly(const char *path) +@@ -121,6 +122,7 @@ extern void mnt_free_filesystems(char ** + + extern char *mnt_get_kernel_cmdline_option(const char *name); + extern int mnt_stat_mountpoint(const char *target, struct stat *st); ++extern FILE *mnt_get_procfs_memstream(int fd, char **membuf); + + /* tab.c */ + extern int is_mountinfo(struct libmnt_table *tb); +diff -up util-linux-2.34/libmount/src/tab_parse.c.kzak util-linux-2.34/libmount/src/tab_parse.c +--- util-linux-2.34/libmount/src/tab_parse.c.kzak 2019-05-09 14:15:40.638552755 +0200 ++++ util-linux-2.34/libmount/src/tab_parse.c 2019-09-13 09:19:54.156419468 +0200 +@@ -698,15 +698,7 @@ static int kernel_fs_postparse(struct li + return rc; + } + +-/** +- * mnt_table_parse_stream: +- * @tb: tab pointer +- * @f: file stream +- * @filename: filename used for debug and error messages +- * +- * Returns: 0 on success, negative number in case of error. +- */ +-int mnt_table_parse_stream(struct libmnt_table *tb, FILE *f, const char *filename) ++static int __table_parse_stream(struct libmnt_table *tb, FILE *f, const char *filename) + { + int rc = -1; + int flags = 0; +@@ -781,6 +773,40 @@ err: + } + + /** ++ * mnt_table_parse_stream: ++ * @tb: tab pointer ++ * @f: file stream ++ * @filename: filename used for debug and error messages ++ * ++ * Returns: 0 on success, negative number in case of error. ++ */ ++int mnt_table_parse_stream(struct libmnt_table *tb, FILE *f, const char *filename) ++{ ++ int fd, rc; ++ FILE *memf = NULL; ++ char *membuf = NULL; ++ ++ /* ++ * For /proc/#/{mountinfo,mount} we read all file to memory and use it ++ * as memory stream. For more details see mnt_read_procfs_file(). ++ */ ++ if ((fd = fileno(f)) >= 0 ++ && (tb->fmt == MNT_FMT_GUESS || ++ tb->fmt == MNT_FMT_MOUNTINFO || ++ tb->fmt == MNT_FMT_MTAB) ++ && is_procfs_fd(fd) ++ && (memf = mnt_get_procfs_memstream(fd, &membuf))) { ++ ++ rc = __table_parse_stream(tb, memf, filename); ++ fclose(memf); ++ free(membuf); ++ } else ++ rc = __table_parse_stream(tb, f, filename); ++ ++ return rc; ++} ++ ++/** + * mnt_table_parse_file: + * @tb: tab pointer + * @filename: file +@@ -795,18 +821,49 @@ err: + int mnt_table_parse_file(struct libmnt_table *tb, const char *filename) + { + FILE *f; +- int rc; ++ int rc, fd = -1; + + if (!filename || !tb) + return -EINVAL; + +- f = fopen(filename, "r" UL_CLOEXECSTR); ++ /* ++ * Try to use read()+poll() to realiably read all ++ * /proc/#/{mount,mountinfo} file to memory ++ */ ++ if (tb->fmt != MNT_FMT_SWAPS ++ && strncmp(filename, "/proc/", 6) == 0) { ++ ++ FILE *memf; ++ char *membuf = NULL; ++ ++ fd = open(filename, O_RDONLY|O_CLOEXEC); ++ if (fd < 0) { ++ rc = -errno; ++ goto done; ++ } ++ memf = mnt_get_procfs_memstream(fd, &membuf); ++ if (memf) { ++ rc = __table_parse_stream(tb, memf, filename); ++ ++ fclose(memf); ++ free(membuf); ++ close(fd); ++ goto done; ++ } ++ /* else fallback to fopen/fdopen() */ ++ } ++ ++ if (fd >= 0) ++ f = fdopen(fd, "r" UL_CLOEXECSTR); ++ else ++ f = fopen(filename, "r" UL_CLOEXECSTR); ++ + if (f) { +- rc = mnt_table_parse_stream(tb, f, filename); ++ rc = __table_parse_stream(tb, f, filename); + fclose(f); + } else + rc = -errno; +- ++done: + DBG(TAB, ul_debugobj(tb, "parsing done [filename=%s, rc=%d]", filename, rc)); + return rc; + } +@@ -863,7 +920,7 @@ static int __mnt_table_parse_dir(struct + + f = fopen_at(dd, d->d_name, O_RDONLY|O_CLOEXEC, "r" UL_CLOEXECSTR); + if (f) { +- mnt_table_parse_stream(tb, f, d->d_name); ++ __table_parse_stream(tb, f, d->d_name); + fclose(f); + } + } +@@ -904,7 +961,7 @@ static int __mnt_table_parse_dir(struct + f = fopen_at(dirfd(dir), d->d_name, + O_RDONLY|O_CLOEXEC, "r" UL_CLOEXECSTR); + if (f) { +- mnt_table_parse_stream(tb, f, d->d_name); ++ __table_parse_stream(tb, f, d->d_name); + fclose(f); + } + } +diff -up util-linux-2.34/libmount/src/utils.c.kzak util-linux-2.34/libmount/src/utils.c +--- util-linux-2.34/libmount/src/utils.c.kzak 2019-06-13 13:26:04.946525187 +0200 ++++ util-linux-2.34/libmount/src/utils.c 2019-09-13 09:19:54.157419462 +0200 +@@ -19,6 +19,7 @@ + #include + #include + #include ++#include + #include + + #include "strutils.h" +@@ -424,6 +425,12 @@ const char *mnt_statfs_get_fstype(struct + return NULL; + } + ++int is_procfs_fd(int fd) ++{ ++ struct statfs sfs; ++ ++ return fstatfs(fd, &sfs) == 0 && sfs.f_type == STATFS_PROC_MAGIC; ++} + + /** + * mnt_match_fstype: +@@ -1140,8 +1147,158 @@ done: + return 1; + } + ++#if defined(HAVE_FMEMOPEN) || defined(TEST_PROGRAM) ++ ++/* ++ * This function tries to minimize possible races when we read ++ * /proc/#/{mountinfo,mount} files. ++ * ++ * The idea is to minimize number of read()s and check by poll() that during ++ * the read the mount table has not been modified. If yes, than re-read it ++ * (with some limitations to avoid never ending loop). ++ * ++ * Returns: <0 error, 0 success, 1 too many attempts ++ */ ++static int read_procfs_file(int fd, char **buf, size_t *bufsiz) ++{ ++ size_t bufmax = 0; ++ int rc = 0, tries = 0, ninters = 0; ++ char *bufptr = NULL;; ++ ++ assert(buf); ++ assert(bufsiz); ++ ++ *bufsiz = 0; ++ *buf = NULL; ++ ++ do { ++ ssize_t ret; ++ ++ if (!bufptr || bufmax == *bufsiz) { ++ char *tmp; ++ ++ bufmax = bufmax ? bufmax * 2 : (16 * 1024); ++ tmp = realloc(*buf, bufmax); ++ if (!tmp) ++ break; ++ *buf = tmp; ++ bufptr = tmp + *bufsiz; ++ } ++ ++ errno = 0; ++ ret = read(fd, bufptr, bufmax - *bufsiz); ++ ++ if (ret < 0) { ++ /* error */ ++ if ((errno == EAGAIN || errno == EINTR) && (ninters++ < 5)) { ++ xusleep(200000); ++ continue; ++ } ++ break; ++ ++ } else if (ret > 0) { ++ /* success -- verify no event during read */ ++ struct pollfd fds[] = { ++ { .fd = fd, .events = POLLPRI } ++ }; ++ ++ rc = poll(fds, 1, 0); ++ if (rc < 0) ++ break; /* poll() error */ ++ if (rc > 0) { ++ /* event -- read all again */ ++ if (lseek(fd, 0, SEEK_SET) != 0) ++ break; ++ *bufsiz = 0; ++ bufptr = *buf; ++ tries++; ++ ++ if (tries > 10) ++ /* busy system? -- wait */ ++ xusleep(10000); ++ continue; ++ } ++ ++ /* successful read() without active poll() */ ++ (*bufsiz) += (size_t) ret; ++ bufptr += ret; ++ tries = ninters = 0; ++ } else { ++ /* end-of-file */ ++ goto success; ++ } ++ } while (tries <= 100); ++ ++ rc = errno ? -errno : 1; ++ free(*buf); ++ return rc; ++ ++success: ++ return 0; ++} ++ ++/* ++ * Create FILE stream for data from read_procfs_file() ++ */ ++FILE *mnt_get_procfs_memstream(int fd, char **membuf) ++{ ++ FILE *memf; ++ size_t sz = 0; ++ off_t cur; ++ ++ /* in case of error, rewind to the original position */ ++ cur = lseek(fd, 0, SEEK_CUR); ++ ++ if (read_procfs_file(fd, membuf, &sz) == 0 ++ && sz > 0 ++ && (memf = fmemopen(*membuf, sz, "r"))) ++ return memf; ++ ++ /* error */ ++ lseek(fd, cur, SEEK_SET); ++ return NULL; ++} ++#else ++FILE *mnt_get_procfs_memstream(int fd __attribute((__unused__)), ++ char **membuf __attribute((__unused__))) ++{ ++ return NULL; ++} ++#endif /* HAVE_FMEMOPEN */ ++ + + #ifdef TEST_PROGRAM ++static int test_proc_read(struct libmnt_test *ts, int argc, char *argv[]) ++{ ++ char *buf = NULL; ++ char *filename = argv[1]; ++ size_t bufsiz = 0; ++ int rc = 0, fd = open(filename, O_RDONLY); ++ ++ if (fd <= 0) { ++ warn("%s: cannot open", filename); ++ return -errno; ++ } ++ ++ rc = read_procfs_file(fd, &buf, &bufsiz); ++ close(fd); ++ ++ switch (rc) { ++ case 0: ++ fwrite(buf, 1, bufsiz, stdout); ++ free(buf); ++ break; ++ case 1: ++ warnx("too many attempts"); ++ break; ++ default: ++ warn("%s: cannot read", filename); ++ break; ++ } ++ ++ return rc; ++} ++ + static int test_match_fstype(struct libmnt_test *ts, int argc, char *argv[]) + { + char *type = argv[1]; +@@ -1323,6 +1480,7 @@ int main(int argc, char *argv[]) + { "--guess-root", test_guess_root, "[]" }, + { "--mkdir", test_mkdir, "" }, + { "--statfs-type", test_statfs_type, "" }, ++ { "--read-procfs", test_proc_read, "" }, + + { NULL } + }; diff --git a/util-linux.spec b/util-linux.spec index e60744c..a3fdee6 100644 --- a/util-linux.spec +++ b/util-linux.spec @@ -2,7 +2,7 @@ Summary: A collection of basic system utilities Name: util-linux Version: 2.34 -Release: 5%{?dist} +Release: 6%{?dist} License: GPLv2 and GPLv2+ and LGPLv2+ and BSD with advertising and Public Domain URL: http://en.wikipedia.org/wiki/Util-linux @@ -41,6 +41,10 @@ BuildRequires: gcc %ifarch ppc64le BuildRequires: librtas-devel %endif +BuildRequires: autoconf +BuildRequires: automake +BuildRequires: libtool +BuildRequires: bison ### Sources Source0: ftp://ftp.kernel.org/pub/linux/utils/util-linux/v%{upstream_major}/util-linux-%{upstream_version}.tar.xz @@ -104,6 +108,8 @@ Patch0: 2.28-login-lastlog-create.patch # 1751290 - regression: lsblk not showing PKNAME in f31+ Patch1: lsblk-force-to-print-PKNAME-for-partition.patch +# https://github.com/systemd/systemd/issues/10872 +Patch2: libmount-improve-mountinfo-reliability.patch %description The util-linux package contains a large variety of low-level system @@ -273,6 +279,12 @@ chfn and chsh utilities with dependence on libuser %build unset LINGUAS || : +# unfortunately, we did changes to build-system +./autogen.sh + +# we modify .po files by RHEL patches +rm -f po/stamp* + export CFLAGS="-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 $RPM_OPT_FLAGS" export SUID_CFLAGS="-fpie" export SUID_LDFLAGS="-pie -Wl,-z,relro -Wl,-z,now" @@ -922,6 +934,9 @@ fi %{_libdir}/python*/site-packages/libmount/ %changelog +* Fri Sep 13 2019 Karel Zak - 2.34-6 +- fix https://github.com/systemd/systemd/issues/10872 + * Thu Sep 12 2019 Karel Zak - 2.34-5 - fix #1751290 - regression: lsblk not showing PKNAME in f31+