fix a leak in replace_fd() users

replace_fd() began with "eats a reference, tries to insert into
descriptor table" semantics; at some point I'd switched it to
much saner current behaviour ("try to insert into descriptor
table, grabbing a new reference if inserted; caller should do
fput() in any case"), but forgot to update the callers.
Mea culpa...

[Spotted by Pavel Roskin, who has really weird system with pipe-fed
coredumps as part of what he considers a normal boot ;-)]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2012-10-16 13:30:07 -04:00
parent dd8e8c4a2c
commit 45525b26a4
2 changed files with 10 additions and 13 deletions

View File

@ -450,11 +450,12 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new)
cp->file = files[1];
replace_fd(0, files[0], 0);
err = replace_fd(0, files[0], 0);
fput(files[0]);
/* and disallow core files too */
current->signal->rlim[RLIMIT_CORE] = (struct rlimit){1, 1};
return 0;
return err;
}
void do_coredump(siginfo_t *siginfo, struct pt_regs *regs)

View File

@ -2132,18 +2132,14 @@ static inline void flush_unauthorized_files(const struct cred *cred,
return;
devnull = dentry_open(&selinux_null, O_RDWR, cred);
if (!IS_ERR(devnull)) {
/* replace all the matching ones with this */
do {
replace_fd(n - 1, get_file(devnull), 0);
} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
if (IS_ERR(devnull))
devnull = NULL;
/* replace all the matching ones with this */
do {
replace_fd(n - 1, devnull, 0);
} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
if (devnull)
fput(devnull);
} else {
/* just close all the matching ones */
do {
replace_fd(n - 1, NULL, 0);
} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
}
}
/*