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Fix Integer overflow in binary CPIO handler #5089

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Fix Integer overflow in binary CPIO handler #5089

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18 changes: 15 additions & 3 deletions src/vfs/cpio/cpio.c
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Original file line number Diff line number Diff line change
Expand Up @@ -518,7 +518,9 @@ cpio_create_entry (struct vfs_class *me, struct vfs_s_super *super, struct stat
// FIXME: do we must read from arch->fd in case of inode != NULL only or in any
// case?

inode->linkname = g_malloc (st->st_size + 1);
if (st->st_size < 0 || (gsize) st->st_size >= G_MAXSIZE)
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@mc-worker mc-worker Apr 16, 2026 •
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Why do you reduce off_t to gsize? I think, sizeof (off_t) >= sizeof (gsize), so the correct way is

st->st_size >= (off_t) G_MAXSIZE

return STATUS_FAIL;
inode->linkname = g_malloc ((gsize) st->st_size + 1);

if (mc_read (arch->fd, inode->linkname, st->st_size) < st->st_size)
{
Expand Down Expand Up @@ -597,7 +599,12 @@ cpio_read_bin_head (struct vfs_class *me, struct vfs_s_super *super)
st.st_rdev = u.buf.c_rdev;
#endif
st.st_size = ((off_t) u.buf.c_filesizes[0] << 16) | u.buf.c_filesizes[1];

if (st.st_size < 0 || st.st_size > MC_MAXPATHLEN)
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@mc-worker mc-worker Apr 16, 2026

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Why do you compare file size with path length? It is correct for link not for regular file,

{
message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
g_free (name);
return STATUS_FAIL;
}
vfs_zero_stat_times (&st);

st.st_atime = st.st_mtime = st.st_ctime =
Expand Down Expand Up @@ -751,7 +758,12 @@ cpio_read_crc_head (struct vfs_class *me, struct vfs_s_super *super)
u.st.st_rdev = makedev (hd.c_rdev, hd.c_rdevmin);
#endif
u.st.st_size = hd.c_filesize;

if (u.st.st_size < 0 || u.st.st_size > MC_MAXPATHLEN)
{
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@mc-worker mc-worker Apr 16, 2026

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Likewise.

message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
g_free (name);
return STATUS_FAIL;
}
vfs_zero_stat_times (&u.st);
u.st.st_atime = u.st.st_mtime = u.st.st_ctime = hd.c_mtime;

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