From b3897f567100d18e0597f638b911d23aa5e0dd23 Mon Sep 17 00:00:00 2001 From: Miloslav Trmac Date: Thu, 19 Mar 2009 09:48:27 -0400 Subject: Audit: fix handling of 'strings' with NULL characters currently audit_log_n_untrustedstring() uses audit_string_contains_control() to check if the 'string' has any control characters. If the 'string' has an embedded NULL audit_string_contains_control() will return that the data has no control characters and will then pass the string to audit_log_n_string with the total length, not the length up to the first NULL. audit_log_n_string() does a memcpy of the entire length and so the actual audit record emitted may then contain a NULL and then whatever random memory is after the NULL. Since we want to log the entire octet stream (if we can't trust the data to be a string we can't trust that a NULL isn't actually a part of it) we should just consider NULL as a control character. If the caller is certain they want to stop at the first NULL they should be using audit_log_untrustedstring. Signed-off-by: Eric Paris Signed-off-by: Al Viro --- kernel/audit.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index ce6d8ea3131e..fa3805516dff 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -1382,7 +1382,7 @@ void audit_log_n_string(struct audit_buffer *ab, const char *string, int audit_string_contains_control(const char *string, size_t len) { const unsigned char *p; - for (p = string; p < (const unsigned char *)string + len && *p; p++) { + for (p = string; p < (const unsigned char *)string + len; p++) { if (*p == '"' || *p < 0x21 || *p > 0x7e) return 1; } -- cgit v1.2.2 From 55ad2f8d340678397de5916b9cd960f17ebd7150 Mon Sep 17 00:00:00 2001 From: Miloslav Trmac Date: Thu, 19 Mar 2009 09:52:47 -0400 Subject: audit: ignore terminating NUL in AUDIT_USER_TTY messages AUDIT_USER_TTY, like all other messages sent from user-space, is sent NUL-terminated. Unlike other user-space audit messages, which come only from trusted sources, AUDIT_USER_TTY messages are processed using audit_log_n_untrustedstring(). This patch modifies AUDIT_USER_TTY handling to ignore the trailing NUL and use the "quoted_string" representation of the message if possible. Signed-off-by: Miloslav Trmac Cc: Eric Paris Cc: Al Viro Cc: Steve Grubb Signed-off-by: Andrew Morton Signed-off-by: Al Viro --- kernel/audit.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index fa3805516dff..5560390cb0f5 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -766,6 +766,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) audit_log_format(ab, " msg="); size = nlmsg_len(nlh); + if (size > 0 && + ((unsigned char *)data)[size - 1] == '\0') + size--; audit_log_n_untrustedstring(ab, data, size); } audit_set_pid(ab, pid); -- cgit v1.2.2 From def57543418a5f47debae28a0a9dea2effc11692 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Tue, 10 Mar 2009 18:00:14 -0400 Subject: Audit: remove spaces from audit_log_d_path audit_log_d_path had spaces in the strings which would be emitted on the error paths. This patch simply replaces those spaces with an _ or removes the needless spaces entirely. Signed-off-by: Eric Paris Signed-off-by: Al Viro --- kernel/audit.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/audit.c') diff --git a/kernel/audit.c b/kernel/audit.c index 5560390cb0f5..9442c3533ba9 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -1440,13 +1440,13 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix, /* We will allow 11 spaces for ' (deleted)' to be appended */ pathname = kmalloc(PATH_MAX+11, ab->gfp_mask); if (!pathname) { - audit_log_format(ab, ""); + audit_log_string(ab, ""); return; } p = d_path(path, pathname, PATH_MAX+11); if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */ /* FIXME: can we save some information here? */ - audit_log_format(ab, ""); + audit_log_string(ab, ""); } else audit_log_untrustedstring(ab, p); kfree(pathname); -- cgit v1.2.2