diff options
| author | H. Peter Anvin <hpa@zytor.com> | 2006-06-26 00:28:02 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-26 09:58:40 -0700 |
| commit | 2139a7fbf3effd8cad505871e3a3c308780ada32 (patch) | |
| tree | 7697089be2d16bab7b59d9f261bad857649a0a10 /init/initramfs.c | |
| parent | 05381954243de2348def8e338ca23fb40a0a721d (diff) | |
[PATCH] initramfs overwrite fix
This patch ensures that initramfs overwrites work correctly, even when dealing
with device nodes of different types. Furthermore, when replacing a file
which already exists, we must make very certain that we truncate the existing
file.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Michael Neuling <mikey@neuling.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'init/initramfs.c')
| -rw-r--r-- | init/initramfs.c | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/init/initramfs.c b/init/initramfs.c index f81cfa40a719..d28c1094d7e5 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -30,6 +30,7 @@ static void __init free(void *where) static __initdata struct hash { int ino, minor, major; + mode_t mode; struct hash *next; char name[N_ALIGN(PATH_MAX)]; } *head[32]; @@ -41,7 +42,8 @@ static inline int hash(int major, int minor, int ino) return tmp & 31; } -static char __init *find_link(int major, int minor, int ino, char *name) +static char __init *find_link(int major, int minor, int ino, + mode_t mode, char *name) { struct hash **p, *q; for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) { @@ -51,14 +53,17 @@ static char __init *find_link(int major, int minor, int ino, char *name) continue; if ((*p)->major != major) continue; + if (((*p)->mode ^ mode) & S_IFMT) + continue; return (*p)->name; } q = (struct hash *)malloc(sizeof(struct hash)); if (!q) panic("can't allocate link hash entry"); - q->ino = ino; - q->minor = minor; q->major = major; + q->minor = minor; + q->ino = ino; + q->mode = mode; strcpy(q->name, name); q->next = NULL; *p = q; @@ -229,13 +234,25 @@ static int __init do_reset(void) static int __init maybe_link(void) { if (nlink >= 2) { - char *old = find_link(major, minor, ino, collected); + char *old = find_link(major, minor, ino, mode, collected); if (old) return (sys_link(old, collected) < 0) ? -1 : 1; } return 0; } +static void __init clean_path(char *path, mode_t mode) +{ + struct stat st; + + if (!sys_newlstat(path, &st) && (st.st_mode^mode) & S_IFMT) { + if (S_ISDIR(st.st_mode)) + sys_rmdir(path); + else + sys_unlink(path); + } +} + static __initdata int wfd; static int __init do_name(void) @@ -248,9 +265,15 @@ static int __init do_name(void) } if (dry_run) return 0; + clean_path(collected, mode); if (S_ISREG(mode)) { - if (maybe_link() >= 0) { - wfd = sys_open(collected, O_WRONLY|O_CREAT, mode); + int ml = maybe_link(); + if (ml >= 0) { + int openflags = O_WRONLY|O_CREAT; + if (ml != 1) + openflags |= O_TRUNC; + wfd = sys_open(collected, openflags, mode); + if (wfd >= 0) { sys_fchown(wfd, uid, gid); sys_fchmod(wfd, mode); @@ -291,6 +314,7 @@ static int __init do_copy(void) static int __init do_symlink(void) { collected[N_ALIGN(name_len) + body_len] = '\0'; + clean_path(collected, 0); sys_symlink(collected + N_ALIGN(name_len), collected); sys_lchown(collected, uid, gid); state = SkipIt; |