[PATCH v3 RFT 1/2] init/do_mounts.c: ignore final \n in name_to_dev_t
From: Sebastian Capella <hidden>
Date: 2013-09-18 23:30:28
Also in:
linux-pm, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
Enhance name_to_dev_t to handle trailing newline characters on device paths. Some inputs to name_to_dev_t may come from userspace where oftentimes a '\n' is appended to the path. Added const to the name buffer in both the function declaration and the prototype to reflect input buffer handling. By handling trailing newlines in name_to_dev_t, userspace buffers may be directly passed to name_to_dev_t without modification. Signed-off-by: Sebastian Capella <redacted> Cc: Pavel Machek <redacted> Cc: "Eric W. Biederman" <redacted> Cc: Serge Hallyn <redacted> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Stephen Warren <redacted> Cc: Jens Axboe <axboe@kernel.dk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> --- include/linux/mount.h | 2 +- init/do_mounts.c | 25 +++++++++++++++++++------ 2 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/include/linux/mount.h b/include/linux/mount.h
index 73005f9..b024d5c 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h@@ -76,6 +76,6 @@ extern struct vfsmount *vfs_kern_mount(struct file_system_type *type, extern void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list); extern void mark_mounts_for_expiry(struct list_head *mounts); -extern dev_t name_to_dev_t(char *name); +extern dev_t name_to_dev_t(const char *name); #endif /* _LINUX_MOUNT_H */
diff --git a/init/do_mounts.c b/init/do_mounts.c
index 816014c..5a031de 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c@@ -143,6 +143,13 @@ static dev_t devt_from_partuuid(const char *uuid_str) clear_root_wait = true; goto done; } + if (uuid_str[cmp.len - 1] == '\n') { + cmp.len--; + if (!cmp.len) { + clear_root_wait = true; + goto done; + } + } dev = class_find_device(&block_class, NULL, &cmp, &match_dev_by_uuid);
@@ -202,12 +209,13 @@ done: * bangs. */ -dev_t name_to_dev_t(char *name) +dev_t name_to_dev_t(const char *name) { char s[32]; char *p; dev_t res = 0; int part; + int n; #ifdef CONFIG_BLOCK if (strncmp(name, "PARTUUID=", 9) == 0) {
@@ -228,7 +236,7 @@ dev_t name_to_dev_t(char *name) goto fail; } else { res = new_decode_dev(simple_strtoul(name, &p, 16)); - if (*p) + if (*p && *p != '\n') goto fail; } goto done;
@@ -236,15 +244,20 @@ dev_t name_to_dev_t(char *name) name += 5; res = Root_NFS; - if (strcmp(name, "nfs") == 0) + if (strncmp(name, "nfs", 3) == 0) goto done; res = Root_RAM0; - if (strcmp(name, "ram") == 0) + if (strncmp(name, "ram", 3) == 0) goto done; - if (strlen(name) > 31) + n = strlen(name); + if (n != 0 && name[n - 1] == '\n') + n--; + if (n > 31) goto fail; - strcpy(s, name); + strncpy(s, name, n); + s[n] = '\0'; + for (p = s; *p; p++) if (*p == '/') *p = '!';
--
1.7.9.5