From b59233e6a3b30c0529d1649c8f7e69790733787d Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 27 Jun 2014 19:32:14 +0200 Subject: [PATCH] coredump: simplify compression logic a bit This also make sure we remove the original coredump temporary file if we successfully managed to compress the coredump. --- src/journal/coredump.c | 149 +++++++++++++++++++++++++---------------- 1 file changed, 90 insertions(+), 59 deletions(-) diff --git a/src/journal/coredump.c b/src/journal/coredump.c index 0dae0afe01a..78e89d33cfe 100644 --- a/src/journal/coredump.c +++ b/src/journal/coredump.c @@ -139,6 +139,8 @@ static int fix_acl(int fd, uid_t uid) { acl_entry_t entry; acl_permset_t permset; + assert(fd >= 0); + if (uid <= SYSTEM_UID_MAX) return 0; @@ -189,6 +191,8 @@ static int fix_xattr(int fd, const char *info[_INFO_LEN]) { int r = 0; unsigned i; + assert(fd >= 0); + /* Attach some metadata to coredumps via extended * attributes. Just because we can. */ @@ -208,8 +212,17 @@ static int fix_xattr(int fd, const char *info[_INFO_LEN]) { #define filename_escape(s) xescape((s), "./ ") -static int fix_permissions(int fd, const char *filename, const char *target, - const char *info[_INFO_LEN], uid_t uid) { +static int fix_permissions( + int fd, + const char *filename, + const char *target, + const char *info[_INFO_LEN], + uid_t uid) { + + assert(fd >= 0); + assert(filename); + assert(target); + assert(info); /* Ignore errors on these */ fchmod(fd, 0640); @@ -231,7 +244,7 @@ static int fix_permissions(int fd, const char *filename, const char *target, static int maybe_remove_external_coredump(const char *filename, off_t size) { - /* Returns 1 if might remove, 0 if will not remove, <0 on error. */ + /* Returns 1 if might remove, 0 if will not remove, < 0 on error. */ if (IN_SET(arg_storage, COREDUMP_STORAGE_EXTERNAL, COREDUMP_STORAGE_BOTH) && size <= arg_external_size_max) @@ -248,6 +261,45 @@ static int maybe_remove_external_coredump(const char *filename, off_t size) { return 1; } +static int make_filename(const char *info[_INFO_LEN], char **ret) { + _cleanup_free_ char *c = NULL, *u = NULL, *p = NULL, *t = NULL; + sd_id128_t boot; + int r; + + assert(info); + + c = filename_escape(info[INFO_COMM]); + if (!c) + return -ENOMEM; + + u = filename_escape(info[INFO_UID]); + if (!u) + return -ENOMEM; + + r = sd_id128_get_boot(&boot); + if (r < 0) + return r; + + p = filename_escape(info[INFO_PID]); + if (!p) + return -ENOMEM; + + t = filename_escape(info[INFO_TIMESTAMP]); + if (!t) + return -ENOMEM; + + if (asprintf(ret, + "/var/lib/systemd/coredump/core.%s.%s." SD_ID128_FORMAT_STR ".%s.%s000000", + c, + u, + SD_ID128_FORMAT_VAL(boot), + p, + t) < 0) + return -ENOMEM; + + return 0; +} + static int save_external_coredump( const char *info[_INFO_LEN], uid_t uid, @@ -255,9 +307,8 @@ static int save_external_coredump( int *ret_fd, off_t *ret_size) { - _cleanup_free_ char *p = NULL, *t = NULL, *c = NULL, *fn = NULL, *tmp = NULL, *u = NULL; + _cleanup_free_ char *fn = NULL, *tmp = NULL; _cleanup_close_ int fd = -1; - sd_id128_t boot; struct stat st; int r; @@ -266,38 +317,12 @@ static int save_external_coredump( assert(ret_fd); assert(ret_size); - c = filename_escape(info[INFO_COMM]); - if (!c) - return log_oom(); - - p = filename_escape(info[INFO_PID]); - if (!p) - return log_oom(); - - u = filename_escape(info[INFO_UID]); - if (!u) - return log_oom(); - - t = filename_escape(info[INFO_TIMESTAMP]); - if (!t) - return log_oom(); - - r = sd_id128_get_boot(&boot); + r = make_filename(info, &fn); if (r < 0) { - log_error("Failed to determine boot ID: %s", strerror(-r)); + log_error("Failed to determine coredump file name: %s", strerror(-r)); return r; } - r = asprintf(&fn, - "/var/lib/systemd/coredump/core.%s.%s." SD_ID128_FORMAT_STR ".%s.%s000000", - c, - u, - SD_ID128_FORMAT_VAL(boot), - p, - t); - if (r < 0) - return log_oom(); - tmp = tempfn_random(fn); if (!tmp) return log_oom(); @@ -329,7 +354,7 @@ static int save_external_coredump( if (lseek(fd, 0, SEEK_SET) == (off_t) -1) { log_error("Failed to seek on %s: %m", tmp); - goto uncompressed; + goto fail; } #ifdef HAVE_XZ @@ -337,45 +362,51 @@ static int save_external_coredump( if (maybe_remove_external_coredump(NULL, st.st_size) == 0 && arg_compress) { - _cleanup_free_ char *fn2 = NULL; - char *tmp2; - _cleanup_close_ int fd2 = -1; + _cleanup_free_ char *fn_compressed = NULL, *tmp_compressed = NULL; + _cleanup_close_ int fd_compressed = -1; - tmp2 = strappenda(tmp, ".xz"); - fd2 = open(tmp2, O_CREAT|O_EXCL|O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0640); - if (fd2 < 0) { - log_error("Failed to create file %s: %m", tmp2); + fn_compressed = strappend(fn, ".xz"); + if (!fn_compressed) { + r = log_oom(); goto uncompressed; } - r = compress_stream(fd, fd2, LZMA_PRESET_DEFAULT, -1); + tmp_compressed = tempfn_random(fn_compressed); + if (!tmp_compressed) { + r = log_oom(); + goto uncompressed; + } + + fd_compressed = open(tmp_compressed, O_CREAT|O_EXCL|O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0640); + if (fd_compressed < 0) { + log_error("Failed to create file %s: %m", tmp_compressed); + goto uncompressed; + } + + r = compress_stream(fd, fd_compressed, LZMA_PRESET_DEFAULT, -1); if (r < 0) { - log_error("Failed to compress %s: %s", tmp2, strerror(-r)); - unlink_noerrno(tmp2); - goto fail2; + log_error("Failed to compress %s: %s", tmp_compressed, strerror(-r)); + goto fail_compressed; } - fn2 = strappend(fn, ".xz"); - if (!fn2) { - log_oom(); - goto fail2; - } - - r = fix_permissions(fd2, tmp2, fn2, info, uid); + r = fix_permissions(fd_compressed, tmp_compressed, fn_compressed, info, uid); if (r < 0) - goto fail2; + goto fail_compressed; - *ret_filename = fn2; /* compressed */ - *ret_fd = fd; /* uncompressed */ - *ret_size = st.st_size; /* uncompressed */ + /* OK, this worked, we can get rid of the uncompressed version now */ + unlink_noerrno(tmp); - fn2 = NULL; + *ret_filename = fn_compressed; /* compressed */ + *ret_fd = fd; /* uncompressed */ + *ret_size = st.st_size; /* uncompressed */ + + fn_compressed = NULL; fd = -1; return 0; - fail2: - unlink_noerrno(tmp2); + fail_compressed: + unlink_noerrno(tmp_compressed); } #endif