From 54dd30e514412198734e8ddf56fca98f078e4fc1 Mon Sep 17 00:00:00 2001 From: "yanjun.zhu" Date: Tue, 11 Dec 2012 18:00:32 +0800 Subject: squashfs: fix CVE-2012-4025 CQID:WIND00366813 Reference: http://squashfs.git.sourceforge.net/git/gitweb.cgi? p=squashfs/squashfs;a=patch;h=8515b3d420f502c5c0236b86e2d6d7e3b23c190e Integer overflow in the queue_init function in unsquashfs.c in unsquashfs in Squashfs 4.2 and earlier allows remote attackers to execute arbitrary code via a crafted block_log field in the superblock of a .sqsh file, leading to a heap-based buffer overflow. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2012-4025 (From OE-Core rev: 4493173c1ab7a0528e0c74935a105e474521ed1c) Signed-off-by: yanjun.zhu [YOCTO #3564] Signed-off-by: Saul Wold Signed-off-by: Richard Purdie --- .../patches/squashfs-4.2-fix-CVE-2012-4025.patch | 190 ++++++++++++++++++ ...dd-a-commment-and-fix-some-other-comments.patch | 38 ++++ .../patches/squashfs-fix-open-file-limit.patch | 215 +++++++++++++++++++++ .../squashfs-tools/squashfs-tools_4.2.bb | 5 +- 4 files changed, 447 insertions(+), 1 deletion(-) create mode 100644 meta/recipes-devtools/squashfs-tools/patches/squashfs-4.2-fix-CVE-2012-4025.patch create mode 100644 meta/recipes-devtools/squashfs-tools/patches/squashfs-add-a-commment-and-fix-some-other-comments.patch create mode 100644 meta/recipes-devtools/squashfs-tools/patches/squashfs-fix-open-file-limit.patch diff --git a/meta/recipes-devtools/squashfs-tools/patches/squashfs-4.2-fix-CVE-2012-4025.patch b/meta/recipes-devtools/squashfs-tools/patches/squashfs-4.2-fix-CVE-2012-4025.patch new file mode 100644 index 0000000000..0dabfba663 --- /dev/null +++ b/meta/recipes-devtools/squashfs-tools/patches/squashfs-4.2-fix-CVE-2012-4025.patch @@ -0,0 +1,190 @@ +Upstream-Status: Backport + +Reference: http://squashfs.git.sourceforge.net/git/gitweb.cgi? +p=squashfs/squashfs;a=patch;h=8515b3d420f502c5c0236b86e2d6d7e3b23c190e + +Integer overflow in the queue_init function in unsquashfs.c in +unsquashfs in Squashfs 4.2 and earlier allows remote attackers +to execute arbitrary code via a crafted block_log field in the +superblock of a .sqsh file, leading to a heap-based buffer overflow. + +http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2012-4025 + +Signed-off-by: yanjun.zhu + +--- a/unsquashfs.c 2012-11-30 17:57:57.000000000 +0800 ++++ b/unsquashfs.c 2012-11-30 17:58:09.000000000 +0800 +@@ -33,6 +33,7 @@ + #include + #include + #include ++#include + + struct cache *fragment_cache, *data_cache; + struct queue *to_reader, *to_deflate, *to_writer, *from_writer; +@@ -138,6 +139,24 @@ void sigalrm_handler() + } + + ++int add_overflow(int a, int b) ++{ ++ return (INT_MAX - a) < b; ++} ++ ++ ++int shift_overflow(int a, int shift) ++{ ++ return (INT_MAX >> shift) < a; ++} ++ ++ ++int multiply_overflow(int a, int multiplier) ++{ ++ return (INT_MAX / multiplier) < a; ++} ++ ++ + struct queue *queue_init(int size) + { + struct queue *queue = malloc(sizeof(struct queue)); +@@ -145,6 +164,10 @@ struct queue *queue_init(int size) + if(queue == NULL) + EXIT_UNSQUASH("Out of memory in queue_init\n"); + ++ if(add_overflow(size, 1) || ++ multiply_overflow(size + 1, sizeof(void *))) ++ EXIT_UNSQUASH("Size too large in queue_init\n"); ++ + queue->data = malloc(sizeof(void *) * (size + 1)); + if(queue->data == NULL) + EXIT_UNSQUASH("Out of memory in queue_init\n"); +@@ -1948,13 +1971,30 @@ void initialise_threads(int fragment_buf + * allocate to_reader, to_deflate and to_writer queues. Set based on + * open file limit and cache size, unless open file limit is unlimited, + * in which case set purely based on cache limits ++ * ++ * In doing so, check that the user supplied values do not overflow ++ * a signed int + */ + if (max_files != -1) { ++ if(add_overflow(data_buffer_size, max_files) || ++ add_overflow(data_buffer_size, max_files * 2)) ++ EXIT_UNSQUASH("Data queue size is too large\n"); ++ + to_reader = queue_init(max_files + data_buffer_size); + to_deflate = queue_init(max_files + data_buffer_size); + to_writer = queue_init(max_files * 2 + data_buffer_size); + } else { +- int all_buffers_size = fragment_buffer_size + data_buffer_size; ++ int all_buffers_size; ++ ++ if(add_overflow(fragment_buffer_size, data_buffer_size)) ++ EXIT_UNSQUASH("Data and fragment queues combined are" ++ " too large\n"); ++ ++ all_buffers_size = fragment_buffer_size + data_buffer_size; ++ ++ if(add_overflow(all_buffers_size, all_buffers_size)) ++ EXIT_UNSQUASH("Data and fragment queues combined are" ++ " too large\n"); + + to_reader = queue_init(all_buffers_size); + to_deflate = queue_init(all_buffers_size); +@@ -2059,6 +2099,32 @@ void progress_bar(long long current, lon + } + + ++int parse_number(char *arg, int *res) ++{ ++ char *b; ++ long number = strtol(arg, &b, 10); ++ ++ /* check for trailing junk after number */ ++ if(*b != '\0') ++ return 0; ++ ++ /* check for strtol underflow or overflow in conversion */ ++ if(number == LONG_MIN || number == LONG_MAX) ++ return 0; ++ ++ /* reject negative numbers as invalid */ ++ if(number < 0) ++ return 0; ++ ++ /* check if long result will overflow signed int */ ++ if(number > INT_MAX) ++ return 0; ++ ++ *res = number; ++ return 1; ++} ++ ++ + #define VERSION() \ + printf("unsquashfs version 4.2 (2011/02/28)\n");\ + printf("copyright (C) 2011 Phillip Lougher "\ +@@ -2140,8 +2206,8 @@ int main(int argc, char *argv[]) + } else if(strcmp(argv[i], "-data-queue") == 0 || + strcmp(argv[i], "-da") == 0) { + if((++i == argc) || +- (data_buffer_size = strtol(argv[i], &b, +- 10), *b != '\0')) { ++ !parse_number(argv[i], ++ &data_buffer_size)) { + ERROR("%s: -data-queue missing or invalid " + "queue size\n", argv[0]); + exit(1); +@@ -2154,8 +2220,8 @@ int main(int argc, char *argv[]) + } else if(strcmp(argv[i], "-frag-queue") == 0 || + strcmp(argv[i], "-fr") == 0) { + if((++i == argc) || +- (fragment_buffer_size = strtol(argv[i], +- &b, 10), *b != '\0')) { ++ !parse_number(argv[i], ++ &fragment_buffer_size)) { + ERROR("%s: -frag-queue missing or invalid " + "queue size\n", argv[0]); + exit(1); +@@ -2280,11 +2346,39 @@ options: + block_log = sBlk.s.block_log; + + /* ++ * Sanity check block size and block log. ++ * ++ * Check they're within correct limits ++ */ ++ if(block_size > SQUASHFS_FILE_MAX_SIZE || ++ block_log > SQUASHFS_FILE_MAX_LOG) ++ EXIT_UNSQUASH("Block size or block_log too large." ++ " File system is corrupt.\n"); ++ ++ /* ++ * Check block_size and block_log match ++ */ ++ if(block_size != (1 << block_log)) ++ EXIT_UNSQUASH("Block size and block_log do not match." ++ " File system is corrupt.\n"); ++ ++ /* + * convert from queue size in Mbytes to queue size in +- * blocks ++ * blocks. ++ * ++ * In doing so, check that the user supplied values do not ++ * overflow a signed int + */ +- fragment_buffer_size <<= 20 - block_log; +- data_buffer_size <<= 20 - block_log; ++ if(shift_overflow(fragment_buffer_size, 20 - block_log)) ++ EXIT_UNSQUASH("Fragment queue size is too large\n"); ++ else ++ fragment_buffer_size <<= 20 - block_log; ++ ++ if(shift_overflow(data_buffer_size, 20 - block_log)) ++ EXIT_UNSQUASH("Data queue size is too large\n"); ++ else ++ data_buffer_size <<= 20 - block_log; ++ + initialise_threads(fragment_buffer_size, data_buffer_size); + + fragment_data = malloc(block_size); diff --git a/meta/recipes-devtools/squashfs-tools/patches/squashfs-add-a-commment-and-fix-some-other-comments.patch b/meta/recipes-devtools/squashfs-tools/patches/squashfs-add-a-commment-and-fix-some-other-comments.patch new file mode 100644 index 0000000000..fa075f9e7d --- /dev/null +++ b/meta/recipes-devtools/squashfs-tools/patches/squashfs-add-a-commment-and-fix-some-other-comments.patch @@ -0,0 +1,38 @@ +Upstream-Status: Backport + +unsquashfs: add a commment and fix some other comments + +Signed-off-by: yanjun.zhu + +diff -urpN a/unsquashfs.c b/unsquashfs.c +--- a/unsquashfs.c 2012-11-30 15:27:14.000000000 +0800 ++++ b/unsquashfs.c 2012-11-30 15:27:56.000000000 +0800 +@@ -814,7 +814,7 @@ int write_file(struct inode *inode, char + + /* + * the writer thread is queued a squashfs_file structure describing the +- * file. If the file has one or more blocks or a fragments they are ++ * file. If the file has one or more blocks or a fragment they are + * queued separately (references to blocks in the cache). + */ + file->fd = file_fd; +@@ -838,7 +838,7 @@ int write_file(struct inode *inode, char + block->offset = 0; + block->size = i == file_end ? inode->data & (block_size - 1) : + block_size; +- if(block_list[i] == 0) /* sparse file */ ++ if(block_list[i] == 0) /* sparse block */ + block->buffer = NULL; + else { + block->buffer = cache_get(data_cache, start, +@@ -2161,6 +2161,10 @@ options: + block_size = sBlk.s.block_size; + block_log = sBlk.s.block_log; + ++ /* ++ * convert from queue size in Mbytes to queue size in ++ * blocks ++ */ + fragment_buffer_size <<= 20 - block_log; + data_buffer_size <<= 20 - block_log; + initialise_threads(fragment_buffer_size, data_buffer_size); diff --git a/meta/recipes-devtools/squashfs-tools/patches/squashfs-fix-open-file-limit.patch b/meta/recipes-devtools/squashfs-tools/patches/squashfs-fix-open-file-limit.patch new file mode 100644 index 0000000000..c60f7b42af --- /dev/null +++ b/meta/recipes-devtools/squashfs-tools/patches/squashfs-fix-open-file-limit.patch @@ -0,0 +1,215 @@ +Upstream-Status: Backport + +unsquashfs: fix open file limit + +Previously Unsquashfs relied on the to_writer queue being +set to 1000 to limit the amount of open file read-ahead to a +maximum of 500. For the default process limit of 1024 open files +this was perhaps acceptable, but it obviously breaks if ulimit has +been used to set the open file limit to below 504 (this includes +stdin, stdout, stderr and the Squashfs filesystem being unsquashed). + +More importantly setting the to_writer queue to 1000 to limit +the amount of files open has always been an inherent performance +hit because the to_writer queue queues blocks. It limits the +block readhead to 1000 blocks, irrespective of how many files +that represents. A single file containing more than 1000 blocks +will still be limited to a 1000 block readahead even though the +data block cache typically can buffer more than this (at the +default data cache size of 256 Mbytes and the default block size +of 128 Kbytes, it can buffer 2048 blocks). Obviously the +caches serve more than just a read-ahead role (they also +cache decompressed blocks in case they're referenced later e.g. +by duplicate files), but the artificial limit imposed on +the read-ahead due to setting the to_writer queue to 1000 is +unnecessary. + +This commit does away with the need to limit the to_writer queue, +by introducing open_wait() and close_wake() calls which correctly +track the amount of open files. + +Signed-off-by: Phillip Lougher + +Signed-off-by: yanjun.zhu + +diff -urpN a/unsquashfs.c b/unsquashfs.c +--- a/unsquashfs.c 2012-11-30 15:31:29.000000000 +0800 ++++ b/unsquashfs.c 2012-11-30 15:32:03.000000000 +0800 +@@ -31,6 +31,8 @@ + + #include + #include ++#include ++#include + + struct cache *fragment_cache, *data_cache; + struct queue *to_reader, *to_deflate, *to_writer, *from_writer; +@@ -784,6 +786,46 @@ failure: + } + + ++pthread_mutex_t open_mutex = PTHREAD_MUTEX_INITIALIZER; ++pthread_cond_t open_empty = PTHREAD_COND_INITIALIZER; ++int open_unlimited, open_count; ++#define OPEN_FILE_MARGIN 10 ++ ++ ++void open_init(int count) ++{ ++ open_count = count; ++ open_unlimited = count == -1; ++} ++ ++ ++int open_wait(char *pathname, int flags, mode_t mode) ++{ ++ if (!open_unlimited) { ++ pthread_mutex_lock(&open_mutex); ++ while (open_count == 0) ++ pthread_cond_wait(&open_empty, &open_mutex); ++ open_count --; ++ pthread_mutex_unlock(&open_mutex); ++ } ++ ++ return open(pathname, flags, mode); ++} ++ ++ ++void close_wake(int fd) ++{ ++ close(fd); ++ ++ if (!open_unlimited) { ++ pthread_mutex_lock(&open_mutex); ++ open_count ++; ++ pthread_cond_signal(&open_empty); ++ pthread_mutex_unlock(&open_mutex); ++ } ++} ++ ++ + int write_file(struct inode *inode, char *pathname) + { + unsigned int file_fd, i; +@@ -794,8 +836,8 @@ int write_file(struct inode *inode, char + + TRACE("write_file: regular file, blocks %d\n", inode->blocks); + +- file_fd = open(pathname, O_CREAT | O_WRONLY | (force ? O_TRUNC : 0), +- (mode_t) inode->mode & 0777); ++ file_fd = open_wait(pathname, O_CREAT | O_WRONLY | ++ (force ? O_TRUNC : 0), (mode_t) inode->mode & 0777); + if(file_fd == -1) { + ERROR("write_file: failed to create file %s, because %s\n", + pathname, strerror(errno)); +@@ -1712,7 +1754,7 @@ void *writer(void *arg) + } + } + +- close(file_fd); ++ close_wake(file_fd); + if(failed == FALSE) + set_attributes(file->pathname, file->mode, file->uid, + file->gid, file->time, file->xattr, force); +@@ -1803,9 +1845,9 @@ void *progress_thread(void *arg) + + void initialise_threads(int fragment_buffer_size, int data_buffer_size) + { +- int i; ++ struct rlimit rlim; ++ int i, max_files, res; + sigset_t sigmask, old_mask; +- int all_buffers_size = fragment_buffer_size + data_buffer_size; + + sigemptyset(&sigmask); + sigaddset(&sigmask, SIGINT); +@@ -1841,10 +1883,86 @@ void initialise_threads(int fragment_buf + EXIT_UNSQUASH("Out of memory allocating thread descriptors\n"); + deflator_thread = &thread[3]; + +- to_reader = queue_init(all_buffers_size); +- to_deflate = queue_init(all_buffers_size); +- to_writer = queue_init(1000); ++ /* ++ * dimensioning the to_reader and to_deflate queues. The size of ++ * these queues is directly related to the amount of block ++ * read-ahead possible. To_reader queues block read requests to ++ * the reader thread and to_deflate queues block decompression ++ * requests to the deflate thread(s) (once the block has been read by ++ * the reader thread). The amount of read-ahead is determined by ++ * the combined size of the data_block and fragment caches which ++ * determine the total number of blocks which can be "in flight" ++ * at any one time (either being read or being decompressed) ++ * ++ * The maximum file open limit, however, affects the read-ahead ++ * possible, in that for normal sizes of the fragment and data block ++ * caches, where the incoming files have few data blocks or one fragment ++ * only, the file open limit is likely to be reached before the ++ * caches are full. This means the worst case sizing of the combined ++ * sizes of the caches is unlikely to ever be necessary. However, is is ++ * obvious read-ahead up to the data block cache size is always possible ++ * irrespective of the file open limit, because a single file could ++ * contain that number of blocks. ++ * ++ * Choosing the size as "file open limit + data block cache size" seems ++ * to be a reasonable estimate. We can reasonably assume the maximum ++ * likely read-ahead possible is data block cache size + one fragment ++ * per open file. ++ * ++ * dimensioning the to_writer queue. The size of this queue is ++ * directly related to the amount of block read-ahead possible. ++ * However, unlike the to_reader and to_deflate queues, this is ++ * complicated by the fact the to_writer queue not only contains ++ * entries for fragments and data_blocks but it also contains ++ * file entries, one per open file in the read-ahead. ++ * ++ * Choosing the size as "2 * (file open limit) + ++ * data block cache size" seems to be a reasonable estimate. ++ * We can reasonably assume the maximum likely read-ahead possible ++ * is data block cache size + one fragment per open file, and then ++ * we will have a file_entry for each open file. ++ */ ++ res = getrlimit(RLIMIT_NOFILE, &rlim); ++ if (res == -1) { ++ ERROR("failed to get open file limit! Defaulting to 1\n"); ++ rlim.rlim_cur = 1; ++ } ++ ++ if (rlim.rlim_cur != RLIM_INFINITY) { ++ /* ++ * leave OPEN_FILE_MARGIN free (rlim_cur includes fds used by ++ * stdin, stdout, stderr and filesystem fd ++ */ ++ if (rlim.rlim_cur <= OPEN_FILE_MARGIN) ++ /* no margin, use minimum possible */ ++ max_files = 1; ++ else ++ max_files = rlim.rlim_cur - OPEN_FILE_MARGIN; ++ } else ++ max_files = -1; ++ ++ /* set amount of available files for use by open_wait and close_wake */ ++ open_init(max_files); ++ ++ /* ++ * allocate to_reader, to_deflate and to_writer queues. Set based on ++ * open file limit and cache size, unless open file limit is unlimited, ++ * in which case set purely based on cache limits ++ */ ++ if (max_files != -1) { ++ to_reader = queue_init(max_files + data_buffer_size); ++ to_deflate = queue_init(max_files + data_buffer_size); ++ to_writer = queue_init(max_files * 2 + data_buffer_size); ++ } else { ++ int all_buffers_size = fragment_buffer_size + data_buffer_size; ++ ++ to_reader = queue_init(all_buffers_size); ++ to_deflate = queue_init(all_buffers_size); ++ to_writer = queue_init(all_buffers_size * 2); ++ } ++ + from_writer = queue_init(1); ++ + fragment_cache = cache_init(block_size, fragment_buffer_size); + data_cache = cache_init(block_size, data_buffer_size); + pthread_create(&thread[0], NULL, reader, NULL); diff --git a/meta/recipes-devtools/squashfs-tools/squashfs-tools_4.2.bb b/meta/recipes-devtools/squashfs-tools/squashfs-tools_4.2.bb index 9922f1ef51..528efed1dd 100644 --- a/meta/recipes-devtools/squashfs-tools/squashfs-tools_4.2.bb +++ b/meta/recipes-devtools/squashfs-tools/squashfs-tools_4.2.bb @@ -8,12 +8,15 @@ LIC_FILES_CHKSUM = "file://../COPYING;md5=0636e73ff0215e8d672dc4c32c317bb3 \ file://../../7zC.txt;beginline=12;endline=16;md5=2056cd6d919ebc3807602143c7449a7c \ " DEPENDS = "attr zlib xz" -PR = "1" +PR = "r2" SRC_URI = "${SOURCEFORGE_MIRROR}/squashfs/squashfs${PV}.tar.gz;name=squashfs \ http://downloads.sourceforge.net/sevenzip/lzma465.tar.bz2;name=lzma \ " SRC_URI += "file://squashfs-4.2-fix-CVE-2012-4024.patch \ + file://squashfs-add-a-commment-and-fix-some-other-comments.patch \ + file://squashfs-fix-open-file-limit.patch \ + file://squashfs-4.2-fix-CVE-2012-4025.patch \ " SRC_URI[squashfs.md5sum] = "1b7a781fb4cf8938842279bd3e8ee852" SRC_URI[squashfs.sha256sum] = "d9e0195aa922dbb665ed322b9aaa96e04a476ee650f39bbeadb0d00b24022e96" -- cgit v1.2.3-54-g00ecf