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-rw-r--r--coreutils/chroot.c4
-rw-r--r--include/libbb.h5
-rw-r--r--include/usage.h2
-rw-r--r--libbb/full_write.c8
-rw-r--r--libbb/isdirectory.c11
-rw-r--r--libbb/read.c10
-rw-r--r--libbb/xfuncs.c6
-rw-r--r--printutils/lpd.c148
-rw-r--r--printutils/lpr.c25
-rw-r--r--runit/chpst.c3
-rw-r--r--util-linux/switch_root.c3
11 files changed, 143 insertions, 82 deletions
diff --git a/coreutils/chroot.c b/coreutils/chroot.c
index a3e70e925..1198a415a 100644
--- a/coreutils/chroot.c
+++ b/coreutils/chroot.c
@@ -19,9 +19,7 @@ int chroot_main(int argc, char **argv)
19 } 19 }
20 20
21 ++argv; 21 ++argv;
22 if (chroot(*argv)) { 22 xchroot(*argv);
23 bb_perror_msg_and_die("cannot change root directory to %s", *argv);
24 }
25 xchdir("/"); 23 xchdir("/");
26 24
27 ++argv; 25 ++argv;
diff --git a/include/libbb.h b/include/libbb.h
index 48937c4b1..1ea2e35be 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -315,6 +315,7 @@ void kill_myself_with_sig(int sig) ATTRIBUTE_NORETURN;
315void xsetgid(gid_t gid); 315void xsetgid(gid_t gid);
316void xsetuid(uid_t uid); 316void xsetuid(uid_t uid);
317void xchdir(const char *path); 317void xchdir(const char *path);
318void xchroot(const char *path);
318void xsetenv(const char *key, const char *value); 319void xsetenv(const char *key, const char *value);
319void xunlink(const char *pathname); 320void xunlink(const char *pathname);
320void xstat(const char *pathname, struct stat *buf); 321void xstat(const char *pathname, struct stat *buf);
@@ -500,6 +501,8 @@ extern void *xrealloc(void *old, size_t size);
500 501
501extern ssize_t safe_read(int fd, void *buf, size_t count); 502extern ssize_t safe_read(int fd, void *buf, size_t count);
502extern ssize_t nonblock_safe_read(int fd, void *buf, size_t count); 503extern ssize_t nonblock_safe_read(int fd, void *buf, size_t count);
504// NB: will return short read on error, not -1,
505// if some data was read before error occurred
503extern ssize_t full_read(int fd, void *buf, size_t count); 506extern ssize_t full_read(int fd, void *buf, size_t count);
504extern void xread(int fd, void *buf, size_t count); 507extern void xread(int fd, void *buf, size_t count);
505extern unsigned char xread_char(int fd); 508extern unsigned char xread_char(int fd);
@@ -514,6 +517,8 @@ extern ssize_t open_read_close(const char *filename, void *buf, size_t count);
514extern void *xmalloc_open_read_close(const char *filename, size_t *sizep); 517extern void *xmalloc_open_read_close(const char *filename, size_t *sizep);
515 518
516extern ssize_t safe_write(int fd, const void *buf, size_t count); 519extern ssize_t safe_write(int fd, const void *buf, size_t count);
520// NB: will return short write on error, not -1,
521// if some data was written before error occurred
517extern ssize_t full_write(int fd, const void *buf, size_t count); 522extern ssize_t full_write(int fd, const void *buf, size_t count);
518extern void xwrite(int fd, const void *buf, size_t count); 523extern void xwrite(int fd, const void *buf, size_t count);
519 524
diff --git a/include/usage.h b/include/usage.h
index 7c9a90e77..359f88d27 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -2055,7 +2055,7 @@ USE_FEATURE_BRCTL_FANCY("\n" \
2055 "SPOOLDIR" 2055 "SPOOLDIR"
2056#define lpd_full_usage \ 2056#define lpd_full_usage \
2057 "Example:" \ 2057 "Example:" \
2058 "\n tcpsvd -E localhost 515 lpd /var/spool" 2058 "\n tcpsvd -E 0 515 softlimit -m 99999 lpd /var/spool"
2059 2059
2060#define lpq_trivial_usage \ 2060#define lpq_trivial_usage \
2061 "[-P queue[@host[:port]]] [-U USERNAME] [-d JOBID...] [-fs]" 2061 "[-P queue[@host[:port]]] [-U USERNAME] [-d JOBID...] [-fs]"
diff --git a/libbb/full_write.c b/libbb/full_write.c
index 7bbacb8ac..7503c8b42 100644
--- a/libbb/full_write.c
+++ b/libbb/full_write.c
@@ -24,8 +24,14 @@ ssize_t full_write(int fd, const void *buf, size_t len)
24 while (len) { 24 while (len) {
25 cc = safe_write(fd, buf, len); 25 cc = safe_write(fd, buf, len);
26 26
27 if (cc < 0) 27 if (cc < 0) {
28 if (total) {
29 /* we already wrote some! */
30 /* user can do another write to know the error code */
31 return total;
32 }
28 return cc; /* write() returns -1 on failure. */ 33 return cc; /* write() returns -1 on failure. */
34 }
29 35
30 total += cc; 36 total += cc;
31 buf = ((const char *)buf) + cc; 37 buf = ((const char *)buf) + cc;
diff --git a/libbb/isdirectory.c b/libbb/isdirectory.c
index b35919869..1d2477f47 100644
--- a/libbb/isdirectory.c
+++ b/libbb/isdirectory.c
@@ -12,7 +12,7 @@
12#include "libbb.h" 12#include "libbb.h"
13 13
14/* 14/*
15 * Return TRUE if a fileName is a directory. 15 * Return TRUE if fileName is a directory.
16 * Nonexistent files return FALSE. 16 * Nonexistent files return FALSE.
17 */ 17 */
18int is_directory(const char *fileName, const int followLinks, struct stat *statBuf) 18int is_directory(const char *fileName, const int followLinks, struct stat *statBuf)
@@ -21,8 +21,8 @@ int is_directory(const char *fileName, const int followLinks, struct stat *statB
21 struct stat astatBuf; 21 struct stat astatBuf;
22 22
23 if (statBuf == NULL) { 23 if (statBuf == NULL) {
24 /* set from auto stack buffer */ 24 /* use auto stack buffer */
25 statBuf = &astatBuf; 25 statBuf = &astatBuf;
26 } 26 }
27 27
28 if (followLinks) 28 if (followLinks)
@@ -30,10 +30,7 @@ int is_directory(const char *fileName, const int followLinks, struct stat *statB
30 else 30 else
31 status = lstat(fileName, statBuf); 31 status = lstat(fileName, statBuf);
32 32
33 if (status < 0 || !(S_ISDIR(statBuf->st_mode))) { 33 status = (status == 0 && S_ISDIR(statBuf->st_mode));
34 status = FALSE;
35 }
36 else status = TRUE;
37 34
38 return status; 35 return status;
39} 36}
diff --git a/libbb/read.c b/libbb/read.c
index 4ad41d589..575446536 100644
--- a/libbb/read.c
+++ b/libbb/read.c
@@ -88,8 +88,14 @@ ssize_t full_read(int fd, void *buf, size_t len)
88 while (len) { 88 while (len) {
89 cc = safe_read(fd, buf, len); 89 cc = safe_read(fd, buf, len);
90 90
91 if (cc < 0) 91 if (cc < 0) {
92 return cc; /* read() returns -1 on failure. */ 92 if (total) {
93 /* we already have some! */
94 /* user can do another read to know the error code */
95 return total;
96 }
97 return cc; /* read() returns -1 on failure. */
98 }
93 if (cc == 0) 99 if (cc == 0)
94 break; 100 break;
95 buf = ((char *)buf) + cc; 101 buf = ((char *)buf) + cc;
diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index 17760a3c3..18e696a7a 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -577,6 +577,12 @@ void xchdir(const char *path)
577 bb_perror_msg_and_die("chdir(%s)", path); 577 bb_perror_msg_and_die("chdir(%s)", path);
578} 578}
579 579
580void xchroot(const char *path)
581{
582 if (chroot(path))
583 bb_perror_msg_and_die("can't change root directory to %s", path);
584}
585
580// Print a warning message if opendir() fails, but don't die. 586// Print a warning message if opendir() fails, but don't die.
581DIR *warn_opendir(const char *path) 587DIR *warn_opendir(const char *path)
582{ 588{
diff --git a/printutils/lpd.c b/printutils/lpd.c
index ed3d9d100..916fd6213 100644
--- a/printutils/lpd.c
+++ b/printutils/lpd.c
@@ -1,6 +1,6 @@
1/* vi: set sw=4 ts=4: */ 1/* vi: set sw=4 ts=4: */
2/* 2/*
3 * micro lpd - a small non-queueing lpd 3 * micro lpd
4 * 4 *
5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com> 5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
6 * 6 *
@@ -8,72 +8,108 @@
8 */ 8 */
9#include "libbb.h" 9#include "libbb.h"
10 10
11// TODO: xmalloc_reads is vulnerable to remote OOM attack!
12
11int lpd_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE; 13int lpd_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE;
12int lpd_main(int argc, char *argv[]) 14int lpd_main(int argc, char *argv[])
13{ 15{
14 char *s; 16 int spooling;
17 char *s, *queue;
18
19 // read command
20 s = xmalloc_reads(STDIN_FILENO, NULL);
21
22 // we understand only "receive job" command
23 if (2 != *s) {
24 unsupported_cmd:
25 printf("Command %02x %s\n",
26 (unsigned char)s[0], "is not supported");
27 return EXIT_FAILURE;
28 }
15 29
16 // goto spool directory
17 // spool directory contains either links to real printer devices or just simple files 30 // spool directory contains either links to real printer devices or just simple files
18 // these links or files are called "queues" 31 // these links or files are called "queues"
19 if (!argv[1]) 32 // OR
20 bb_show_usage(); 33 // if a directory named as given queue exists within spool directory
34 // then LPD enters spooling mode and just dumps both control and data files to it
21 35
22 xchdir(argv[1]); 36 // goto spool directory
37 if (argv[1])
38 xchdir(argv[1]);
23 39
24 xdup2(1, 2); 40 // parse command: "\x2QUEUE_NAME\n"
41 queue = s + 1;
42 *strchrnul(s, '\n') = '\0';
25 43
26 // read command 44 // protect against "/../" attacks
27 s = xmalloc_reads(STDIN_FILENO, NULL); 45 if (queue[0] == '.' || strstr(queue, "/."))
46 return EXIT_FAILURE;
28 47
29 // N.B. we keep things simple 48 // queue is a directory -> chdir to it and enter spooling mode
30 // only "receive job" command is meaningful here... 49 spooling = chdir(queue) + 1; /* 0: cannot chdir, 1: done */
31 if (2 == *s) {
32 char *queue;
33 50
34 // parse command: "\x2QUEUE_NAME\n" 51 xdup2(STDOUT_FILENO, STDERR_FILENO);
35 queue = s + 1;
36 *strchrnul(s, '\n') = '\0';
37 52
38 while (1) { 53 while (1) {
39 // signal OK 54 char *fname;
40 write(STDOUT_FILENO, "", 1); 55 int fd;
41 // get subcommand 56 // int is easier than ssize_t: can use xatoi_u,
42 s = xmalloc_reads(STDIN_FILENO, NULL); 57 // and can correctly display error returns (-1)
43 if (!s) 58 int expected_len, real_len;
44 return EXIT_SUCCESS; // EOF (probably) 59
45 // valid s must be of form: SUBCMD | LEN | SP | FNAME 60 // signal OK
46 // N.B. we bail out on any error 61 write(STDOUT_FILENO, "", 1);
47 // control or data file follows 62
48 if (2 == s[0] || 3 == s[0]) { 63 // get subcommand
49 int fd; 64 s = xmalloc_reads(STDIN_FILENO, NULL);
50 size_t len; 65 if (!s)
51 // 2: control file (ignoring), 3: data file 66 return EXIT_SUCCESS; // probably EOF
52 fd = -1; 67 // we understand only "control file" or "data file" cmds
53 if (3 == s[0]) 68 if (2 != s[0] && 3 != s[0])
54 fd = xopen(queue, O_RDWR | O_APPEND); 69 goto unsupported_cmd;
55 // get data length
56 *strchrnul(s, ' ') = '\0';
57 len = xatou(s + 1);
58 // dump exactly len bytes to file, or die
59 bb_copyfd_exact_size(STDIN_FILENO, fd, len);
60 close(fd); // NB: can do close(-1). Who cares?
61 free(s);
62 // got no ACK? -> bail out
63 if (safe_read(STDIN_FILENO, s, 1) <= 0 || s[0]) {
64 // don't talk to peer - it obviously
65 // don't follow the protocol
66 return EXIT_FAILURE;
67 }
68 } else {
69 // any other subcommand aborts receiving job
70 // N.B. abort subcommand itself doesn't contain
71 // fname so it failed earlier...
72 break;
73 }
74 }
75 }
76 70
77 printf("Command %02x not supported\n", (unsigned char)*s); 71 *strchrnul(s, '\n') = '\0';
78 return EXIT_FAILURE; 72 // valid s must be of form: SUBCMD | LEN | SP | FNAME
73 // N.B. we bail out on any error
74 fname = strchr(s, ' ');
75 if (!fname) {
76 printf("Command %02x %s\n",
77 (unsigned char)s[0], "lacks filename");
78 return EXIT_FAILURE;
79 }
80 *fname++ = '\0';
81 if (spooling) {
82 // spooling mode: dump both files
83 // make "/../" attacks in file names ineffective
84 xchroot(".");
85 // job in flight has mode 0200 "only writable"
86 fd = xopen3(fname, O_CREAT | O_WRONLY | O_TRUNC | O_EXCL, 0200);
87 } else {
88 // non-spooling mode:
89 // 2: control file (ignoring), 3: data file
90 fd = -1;
91 if (3 == s[0])
92 fd = xopen(queue, O_RDWR | O_APPEND);
93 }
94 expected_len = xatoi_u(s + 1);
95 real_len = bb_copyfd_size(STDIN_FILENO, fd, expected_len);
96 if (spooling && real_len != expected_len) {
97 unlink(fname); // don't keep corrupted files
98 printf("Expected %d but got %d bytes\n",
99 expected_len, real_len);
100 return EXIT_FAILURE;
101 }
102 // get ACK and see whether it is NUL (ok)
103 if (read(STDIN_FILENO, s, 1) != 1 || s[0] != 0) {
104 // don't send error msg to peer - it obviously
105 // don't follow the protocol, so probably
106 // it can't understand us either
107 return EXIT_FAILURE;
108 }
109 // chmod completely downloaded job as "readable+writable"
110 if (spooling)
111 fchmod(fd, 0600);
112 close(fd); // NB: can do close(-1). Who cares?
113 free(s);
114 } /* while (1) */
79} 115}
diff --git a/printutils/lpr.c b/printutils/lpr.c
index 52983bfb7..09fbc6ad1 100644
--- a/printutils/lpr.c
+++ b/printutils/lpr.c
@@ -19,19 +19,26 @@
19 */ 19 */
20static void get_response_or_say_and_die(const char *errmsg) 20static void get_response_or_say_and_die(const char *errmsg)
21{ 21{
22 static const char newline = '\n'; 22 ssize_t sz;
23 char buf = ' '; 23 char buf[128];
24 24
25 fflush(stdout); 25 fflush(stdout);
26 26
27 safe_read(STDOUT_FILENO, &buf, 1); 27 buf[0] = ' ';
28 if ('\0' != buf) { 28 sz = safe_read(STDOUT_FILENO, buf, 1);
29 if ('\0' != buf[0]) {
29 // request has failed 30 // request has failed
30 bb_error_msg("error while %s. Server said:", errmsg); 31 // try to make sure last char is '\n', but do not add
31 safe_write(STDERR_FILENO, &buf, 1); 32 // superfluous one
32 logmode = 0; /* no error messages from bb_copyfd_eof() pls */ 33 sz = full_read(STDOUT_FILENO, buf + 1, 126);
33 bb_copyfd_eof(STDOUT_FILENO, STDERR_FILENO); 34 bb_error_msg("error while %s%s", errmsg,
34 safe_write(STDERR_FILENO, &newline, 1); 35 (sz > 0 ? ". Server said:" : ""));
36 if (sz > 0) {
37 // sz = (bytes in buf) - 1
38 if (buf[sz] != '\n')
39 buf[++sz] = '\n';
40 safe_write(STDERR_FILENO, buf, sz + 1);
41 }
35 xfunc_die(); 42 xfunc_die();
36 } 43 }
37} 44}
diff --git a/runit/chpst.c b/runit/chpst.c
index 0f605cc45..7b70a4d5a 100644
--- a/runit/chpst.c
+++ b/runit/chpst.c
@@ -332,8 +332,7 @@ int chpst_main(int argc, char **argv)
332 if (env_dir) edir(env_dir); 332 if (env_dir) edir(env_dir);
333 if (root) { 333 if (root) {
334 xchdir(root); 334 xchdir(root);
335 if (chroot(".") == -1) 335 xchroot(".");
336 bb_perror_msg_and_die("chroot");
337 } 336 }
338 slimit(); 337 slimit();
339 if (nicelvl) { 338 if (nicelvl) {
diff --git a/util-linux/switch_root.c b/util-linux/switch_root.c
index bd1e9d5ce..3a1741179 100644
--- a/util-linux/switch_root.c
+++ b/util-linux/switch_root.c
@@ -105,8 +105,9 @@ int switch_root_main(int argc, char **argv)
105 // Overmount / with newdir and chroot into it. The chdir is needed to 105 // Overmount / with newdir and chroot into it. The chdir is needed to
106 // recalculate "." and ".." links. 106 // recalculate "." and ".." links.
107 107
108 if (mount(".", "/", NULL, MS_MOVE, NULL) || chroot(".")) 108 if (mount(".", "/", NULL, MS_MOVE, NULL))
109 bb_error_msg_and_die("error moving root"); 109 bb_error_msg_and_die("error moving root");
110 xchroot(".");
110 xchdir("/"); 111 xchdir("/");
111 112
112 // If a new console specified, redirect stdin/stdout/stderr to that. 113 // If a new console specified, redirect stdin/stdout/stderr to that.
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-03-18 23:10:51 +0000