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190644e180
kernel-aes67/drivers/char
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Jesper Juhl 190644e180 Fix "use after free" / "double free" bug in ati_create_gatt_pages / ati_free_gatt_pages 
Hi,

Coverity spotted a "use after free" bug in
drivers/char/agp/ati-agp.c::ati_create_gatt_pages().

The same one that was in
  drivers/char/agp/amd-k7-agp.c::amd_create_gatt_pages()

The problem is this:
       If "entry = kzalloc(sizeof(struct ati_page_map), GFP_KERNEL);"
fails, then there's a loop in the function to free all entries
allocated so far and break out of the allocation loop. That in itself
is pretty sane, but then the (now freed) 'tables' is assigned to
ati_generic_private.gatt_pages and 'retval' is set to -ENOMEM which
causes ati_free_gatt_pages(); to be called at the end of the function.
The problem with this is that ati_free_gatt_pages() will then loop
'ati_generic_private.num_tables' times and try to free each entry in
tables[] - this is bad since tables has already been freed and
furthermore it will call kfree(tables) at the end - a double free.

This patch removes the freeing loop in ati_create_gatt_pages() and
instead relies entirely on the call to ati_free_gatt_pages() to free
everything we allocated in case of an error. It also sets
ati_generic_private.num_tables to the actual number of entries
allocated instead of just using the value passed in from the caller -
this ensures that ati_free_gatt_pages() will only attempt to free
stuff that was actually allocated.

Note: I'm in no way intimate with this code and I have no way to
actually test this patch (besides compile test it), so while I've
tried to be careful in reading the code and make sure the patch
does the right thing an ACK from someone who actually knows the
code in-depth would be very much appreciated.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
2007-07-27 10:44:32 +10:00
..
agp Fix "use after free" / "double free" bug in ati_create_gatt_pages / ati_free_gatt_pages 2007-07-27 10:44:32 +10:00
drm some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
hw_random x86_64: Geode HW Random Number Generator depends on X86_32 2007-07-21 18:37:13 -07:00
ip2 unregister_chrdev(): ignore the return value 2007-07-19 10:04:43 -07:00
ipmi some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
mwave
pcmcia some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
rio some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
tpm Fix memory leak in tpm_binary_bios_measurements_open() 2007-07-20 12:00:04 -07:00
watchdog Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm 2007-07-22 11:22:59 -07:00
.gitignore
amiserial.c some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
apm-emulation.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
applicom.c
applicom.h
briq_panel.c [POWERPC] Remove dead code for preventing pread() and pwrite() calls 2007-07-10 22:03:26 +10:00
cd1865.h
ChangeLog
consolemap.c Kernel utf-8 handling 2007-07-16 09:05:46 -07:00
cp437.uni
cs5535_gpio.c Char: cs5535_gpio, add MODULE_DEVICE_TABLE 2007-05-08 11:15:04 -07:00
cyclades.c drivers/*: mark variables with uninitialized_var() 2007-07-17 16:23:19 -04:00
defkeymap.c_shipped
defkeymap.map
digi1.h
digiFep1.h
digiPCI.h
ds1286.c
ds1302.c
ds1620.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
dsp56k.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
dtlk.c dtlk: fix error checks in module_init() 2007-05-08 11:15:09 -07:00
ec3104_keyb.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
efirtc.c
epca.c drivers/char: use __set_current_state() 2007-05-08 11:15:13 -07:00
epca.h
epcaconfig.h
esp.c some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
generic_nvram.c
generic_serial.c genericserial: remove bogus optimisation check and dead code paths 2007-07-16 09:05:51 -07:00
genrtc.c Char: genrtc, use wait_event_interruptible 2007-07-16 09:05:44 -07:00
hangcheck-timer.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
hpet.c use CLOCKSOURCE_MASK() instead of too large constant 2007-07-26 11:11:57 -07:00
hvc_beat.c
hvc_console.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
hvc_console.h
hvc_iseries.c [POWERPC] init and exit markings for hvc_iseries 2007-07-22 21:30:59 +10:00
hvc_lguest.c lguest: documentation VII: FIXMEs 2007-07-26 11:35:17 -07:00
hvc_rtas.c [POWERPC] Quiet section mismatch in hvc_rtas.c 2007-07-22 21:30:59 +10:00
hvc_vio.c
hvc_xen.c xen: use the hvc console infrastructure for Xen console 2007-07-18 08:47:44 -07:00
hvcs.c [POWERPC] hvcs: Make some things static and const 2007-07-22 21:30:59 +10:00
hvsi.c
i8k.c i386: sched.h inclusion from module.h is baack 2007-05-08 11:15:08 -07:00
ip27-rtc.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
isicom.c Char: isicom, proper variables types 2007-07-17 10:23:10 -07:00
istallion.c Char: istallion, init+locking fixes 2007-07-17 10:23:10 -07:00
Kconfig Char: cyclades, select FW_LOADER 2007-07-26 11:35:19 -07:00
keyboard.c Kernel utf-8 handling 2007-07-16 09:05:46 -07:00
lcd.c
lcd.h
lp.c ROUND_UP macro cleanup in drivers/char/lp.c 2007-05-08 11:15:08 -07:00
Makefile [SPARC32]: Deal with rtc/sun_mostek_rtc conflict. 2007-07-24 13:24:32 -07:00
mbcs.c mbcs: Remove lots of global symbols 2007-07-19 10:04:43 -07:00
mbcs.h mbcs: Remove lots of global symbols 2007-07-19 10:04:43 -07:00
mem.c Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus 2007-07-10 14:48:43 -07:00
misc.c Make /proc/misc use seq_list_xxx helpers 2007-07-16 09:05:42 -07:00
mmtimer.c [IA64-SN2][KJ] mmtimer.c-kzalloc 2007-05-08 11:53:27 -07:00
moxa.c Char: moxa, eliminate busy waiting 2007-07-17 10:23:10 -07:00
mspec.c mspec_mmap: don't set VM_LOCKED 2007-07-16 09:05:36 -07:00
mxser_new.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
mxser_new.h
mxser.c serial: remove termios checks from various old char serial drivers 2007-07-16 09:05:52 -07:00
mxser.h
n_hdlc.c Char: n_hdlc, allow RESTARTSYS retval of tty write 2007-07-16 09:05:43 -07:00
n_r3964.c Char: n_r3964, use wait_event_interruptible 2007-07-16 09:05:44 -07:00
n_tty.c Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
nsc_gpio.c
nvram.c COBALT: remove all references to Cobalt NVRAM 2007-07-16 09:05:47 -07:00
nwbutton.c
nwbutton.h
nwflash.c
pc8736x_gpio.c
ppdev.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
ps3flash.c ps3: FLASH ROM Storage Driver 2007-07-21 17:49:16 -07:00
pty.c
random.c random: fix bound check ordering (CVE-2007-3105) 2007-07-19 14:21:04 -07:00
raw.c
riscom8_reg.h
riscom8.c Char: riscom8, eliminate busy loop 2007-07-17 10:23:10 -07:00
riscom8.h
rocket_int.h Kill unused sesssion and group values in rocket driver 2007-05-11 08:29:36 -07:00
rocket.c some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
rocket.h
rtc.c x86_64: Untangle asm/hpet.h from asm/timex.h 2007-07-21 18:37:08 -07:00
scc.h
scx200_gpio.c
selection.c Kernel utf-8 handling 2007-07-16 09:05:46 -07:00
ser_a2232.c
ser_a2232.h
ser_a2232fw.ax
ser_a2232fw.h
serial167.c m68k: remove empty ->setup is several consoles 2007-07-20 08:24:49 -07:00
snsc_event.c [IA64] drivers/char/snsc_event.c:206: warning: unused variable `p' 2007-05-10 13:23:05 -07:00
snsc.c
snsc.h
sonypi.c remove sonypi_camera_command() 2007-07-16 09:05:46 -07:00
specialix_io8.h
specialix.c Char: specialix, remove busy waiting 2007-07-17 10:23:10 -07:00
stallion.c unregister_chrdev(): ignore the return value 2007-07-19 10:04:43 -07:00
sx.c sx: switch subven and subid values 2007-07-10 17:51:13 -07:00
sx.h
sxboards.h
sxwindow.h
synclink_gt.c some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
synclink.c some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
synclinkmp.c some kmalloc/memset ->kzalloc (tree wide) 2007-07-19 10:04:50 -07:00
sysrq.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
tb0219.c
tipar.c layered parport code uses parport->dev 2007-05-08 11:15:05 -07:00
tlclk.c
toshiba.c
tty_audit.c Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
tty_io.c Audit: add TTY input auditing 2007-07-16 09:05:47 -07:00
tty_ioctl.c Char: tty_ioctl, little whitespace cleanup 2007-07-16 09:05:44 -07:00
vc_screen.c use mutex instead of semaphore in virtual console driver 2007-05-08 11:15:33 -07:00
viocons.c
viotape.c unregister_chrdev(): ignore the return value 2007-07-19 10:04:43 -07:00
vme_scc.c m68k: remove empty ->setup is several consoles 2007-07-20 08:24:49 -07:00
vr41xx_giu.c [MIPS] Separate platform_device registration for VR41xx GPIO 2007-07-12 17:41:15 +01:00
vt_ioctl.c drivers/char: use __set_current_state() 2007-05-08 11:15:13 -07:00
vt.c Fix the graphic corruption issue on IA64 machines 2007-07-17 10:23:13 -07:00