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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-04 09:30:50 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-04 09:30:50 -0700 |
| commit | b7e14164417865e24b6a1b09110b63c01158fc8e (patch) | |
| tree | cc178532e1fb17249f6ed71dda6764a5c489a804 /fs/binfmt_misc.c | |
| parent | 6c795b30f46ff7efec0039095045c2012416670e (diff) | |
| parent | 32e57c29e3c038ac802b7cc214a8795a4234055f (diff) | |
| download | lwn-b7e14164417865e24b6a1b09110b63c01158fc8e.tar.gz lwn-b7e14164417865e24b6a1b09110b63c01158fc8e.zip | |
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"A lot of stuff, sorry about that. A week on a beach, then a bunch of
time catching up then more time letting it bake in -next. Shan't do
that again!"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (51 commits)
include/linux/fs.h: fix comment about struct address_space
checkpatch: fix ignoring cover-letter logic
m32r: fix build failure
lib/ratelimit.c: use deferred printk() version
kernel/params.c: improve STANDARD_PARAM_DEF readability
kernel/params.c: fix an overflow in param_attr_show
kernel/params.c: fix the maximum length in param_get_string
mm/memory_hotplug: define find_{smallest|biggest}_section_pfn as unsigned long
mm/memory_hotplug: change pfn_to_section_nr/section_nr_to_pfn macro to inline function
kernel/kcmp.c: drop branch leftover typo
memremap: add scheduling point to devm_memremap_pages
mm, page_alloc: add scheduling point to memmap_init_zone
mm, memory_hotplug: add scheduling point to __add_pages
lib/idr.c: fix comment for idr_replace()
mm: memcontrol: use vmalloc fallback for large kmem memcg arrays
kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv()
include/linux/bitfield.h: remove 32bit from FIELD_GET comment block
lib/lz4: make arrays static const, reduces object code size
exec: binfmt_misc: kill the onstack iname[BINPRM_BUF_SIZE] array
exec: binfmt_misc: fix race between load_misc_binary() and kill_node()
...
Diffstat (limited to 'fs/binfmt_misc.c')
| -rw-r--r-- | fs/binfmt_misc.c | 56 |
1 files changed, 26 insertions, 30 deletions
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c index ce7181ea60fa..2a46762def31 100644 --- a/fs/binfmt_misc.c +++ b/fs/binfmt_misc.c @@ -54,7 +54,7 @@ typedef struct { int size; /* size of magic/mask */ char *magic; /* magic or filename extension */ char *mask; /* mask, NULL for exact match */ - char *interpreter; /* filename of interpreter */ + const char *interpreter; /* filename of interpreter */ char *name; struct dentry *dentry; struct file *interp_file; @@ -131,27 +131,26 @@ static int load_misc_binary(struct linux_binprm *bprm) { Node *fmt; struct file *interp_file = NULL; - char iname[BINPRM_BUF_SIZE]; - const char *iname_addr = iname; int retval; int fd_binary = -1; retval = -ENOEXEC; if (!enabled) - goto ret; + return retval; /* to keep locking time low, we copy the interpreter string */ read_lock(&entries_lock); fmt = check_file(bprm); if (fmt) - strlcpy(iname, fmt->interpreter, BINPRM_BUF_SIZE); + dget(fmt->dentry); read_unlock(&entries_lock); if (!fmt) - goto ret; + return retval; /* Need to be able to load the file after exec */ + retval = -ENOENT; if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE) - return -ENOENT; + goto ret; if (!(fmt->flags & MISC_FMT_PRESERVE_ARGV0)) { retval = remove_arg_zero(bprm); @@ -195,22 +194,22 @@ static int load_misc_binary(struct linux_binprm *bprm) bprm->argc++; /* add the interp as argv[0] */ - retval = copy_strings_kernel(1, &iname_addr, bprm); + retval = copy_strings_kernel(1, &fmt->interpreter, bprm); if (retval < 0) goto error; bprm->argc++; /* Update interp in case binfmt_script needs it. */ - retval = bprm_change_interp(iname, bprm); + retval = bprm_change_interp(fmt->interpreter, bprm); if (retval < 0) goto error; - if (fmt->flags & MISC_FMT_OPEN_FILE && fmt->interp_file) { + if (fmt->flags & MISC_FMT_OPEN_FILE) { interp_file = filp_clone_open(fmt->interp_file); if (!IS_ERR(interp_file)) deny_write_access(interp_file); } else { - interp_file = open_exec(iname); + interp_file = open_exec(fmt->interpreter); } retval = PTR_ERR(interp_file); if (IS_ERR(interp_file)) @@ -238,6 +237,7 @@ static int load_misc_binary(struct linux_binprm *bprm) goto error; ret: + dput(fmt->dentry); return retval; error: if (fd_binary > 0) @@ -594,8 +594,13 @@ static struct inode *bm_get_inode(struct super_block *sb, int mode) static void bm_evict_inode(struct inode *inode) { + Node *e = inode->i_private; + + if (e->flags & MISC_FMT_OPEN_FILE) + filp_close(e->interp_file, NULL); + clear_inode(inode); - kfree(inode->i_private); + kfree(e); } static void kill_node(Node *e) @@ -603,24 +608,14 @@ static void kill_node(Node *e) struct dentry *dentry; write_lock(&entries_lock); - dentry = e->dentry; - if (dentry) { - list_del_init(&e->list); - e->dentry = NULL; - } + list_del_init(&e->list); write_unlock(&entries_lock); - if ((e->flags & MISC_FMT_OPEN_FILE) && e->interp_file) { - filp_close(e->interp_file, NULL); - e->interp_file = NULL; - } - - if (dentry) { - drop_nlink(d_inode(dentry)); - d_drop(dentry); - dput(dentry); - simple_release_fs(&bm_mnt, &entry_count); - } + dentry = e->dentry; + drop_nlink(d_inode(dentry)); + d_drop(dentry); + dput(dentry); + simple_release_fs(&bm_mnt, &entry_count); } /* /<entry> */ @@ -665,7 +660,8 @@ static ssize_t bm_entry_write(struct file *file, const char __user *buffer, root = file_inode(file)->i_sb->s_root; inode_lock(d_inode(root)); - kill_node(e); + if (!list_empty(&e->list)) + kill_node(e); inode_unlock(d_inode(root)); break; @@ -794,7 +790,7 @@ static ssize_t bm_status_write(struct file *file, const char __user *buffer, inode_lock(d_inode(root)); while (!list_empty(&entries)) - kill_node(list_entry(entries.next, Node, list)); + kill_node(list_first_entry(&entries, Node, list)); inode_unlock(d_inode(root)); break; |