kernel/linux.git/drivers/auxdisplay, branch v6.12.93

auxdisplay: line-display: fix OOB read on zero-length message_store()

2026-06-09T10:25:49+00:00

commit a7511dcd9dd4bc55d123f9b800c8a4ed2662e5c6 upstream. linedisp_display() unconditionally reads msg[count - 1] before checking whether count is zero, so a write of zero bytes to the message sysfs attribute hits msg[-1]: write(fd, "", 0); -> message_store(..., buf, count=0) -> linedisp_display(linedisp, buf, count=0) -> msg[count - 1] == '\n' ; OOB read The kernfs write buffer for that store is a 1-byte allocation (kernfs_fop_write_iter() does kmalloc(len + 1) with len == 0), so msg[-1] is a 1-byte read before the slab object. On a KASAN-enabled kernel this trips an out-of-bounds report and panics; on stock kernels it silently reads adjacent slab data and, if that byte happens to be '\n', the following count-- wraps ssize_t 0 to -1 and is then passed to kmemdup_nul(). linedisp_display() is reached from the message_store() sysfs callback (drivers/auxdisplay/line-display.c message attribute, mode 0644) and from the in-tree initial-message setup with count == -1, so the OOB path is only userspace-triggerable via zero-byte writes; vfs_write() does not short-circuit on count == 0 and kernfs_fop_write_iter() dispatches the store callback regardless. Guard the trailing-newline trim with a count check. The existing if (!count) block then takes the clear-display path unchanged. Affects every auxdisplay driver that registers via linedisp_register() / linedisp_attach(): ht16k33, max6959, img-ascii-lcd, seg-led-gpio. Fixes: 7e76aece6f03 ("auxdisplay: Extract character line display core support") Signed-off-by: Stepan Ionichev Signed-off-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman

auxdisplay: arm-charlcd: fix release_mem_region() size

2026-03-04T12:19:21+00:00

[ Upstream commit b5c23a4d291d2ac1dfdd574a68a3a68c8da3069e ] It seems like, after the request_mem_region(), the corresponding release_mem_region() must take the same size. This was done in (now removed due to previous refactoring) charlcd_remove() but not in the error path in charlcd_probe(). Fixes: ce8962455e90 ("ARM: 6214/2: driver for the character LCD found in ARM refdesigns") Signed-off-by: Thomas Fourier Reviewed-by: Geert Uytterhoeven Signed-off-by: Andy Shevchenko Signed-off-by: Sasha Levin

auxdisplay: charlcd: Partially revert "Move hwidth and bwidth to struct hd44780_common"

2025-05-29T09:02:24+00:00

[ Upstream commit 09965a142078080fe7807bab0f6f1890cb5987a4 ] Commit 2545c1c948a6 ("auxdisplay: Move hwidth and bwidth to struct hd44780_common") makes charlcd_alloc() argument-less effectively dropping the single allocation for the struct charlcd_priv object along with the driver specific one. Restore that behaviour here. Signed-off-by: Andy Shevchenko Reviewed-by: Geert Uytterhoeven Signed-off-by: Sasha Levin

auxdisplay: hd44780: Fix an API misuse in hd44780.c

2025-04-20T08:15:31+00:00

commit 9b98a7d2e5f4e2beeff88f6571da0cdc5883c7fb upstream. Variable allocated by charlcd_alloc() should be released by charlcd_free(). The following patch changed kfree() to charlcd_free() to fix an API misuse. Fixes: 718e05ed92ec ("auxdisplay: Introduce hd44780_common.[ch]") Cc: stable@vger.kernel.org Signed-off-by: Haoxiang Li Reviewed-by: Geert Uytterhoeven Signed-off-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman

auxdisplay: panel: Fix an API misuse in panel.c

2025-04-10T12:39:12+00:00

[ Upstream commit 72e1c440c848624ad4cfac93d69d8a999a20355b ] Variable allocated by charlcd_alloc() should be released by charlcd_free(). The following patch changed kfree() to charlcd_free() to fix an API misuse. Reviewed-by: Geert Uytterhoeven Fixes: 718e05ed92ec ("auxdisplay: Introduce hd44780_common.[ch]") Signed-off-by: Andy Shevchenko Signed-off-by: Sasha Levin

auxdisplay: MAX6959 should select BITREVERSE

2025-04-10T12:39:12+00:00

[ Upstream commit fce85f3da08b76c1b052f53a9f6f9c40a8a10660 ] If CONFIG_BITREVERSE is not enabled: max6959.c:(.text+0x92): undefined reference to `byte_rev_table' Fixes: a9bcd02fa42217c7 ("auxdisplay: Add driver for MAX695x 7-segment LED controllers") Reported-by: kernel test robot Closes: https://lore.kernel.org/202502161703.3Vr4M7qg-lkp@intel.com/ Signed-off-by: Geert Uytterhoeven Signed-off-by: Andy Shevchenko Signed-off-by: Sasha Levin

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

[tree-wide] finally take no_llseek out

2024-09-27T15:18:43+00:00

no_llseek had been defined to NULL two years ago, in commit 868941b14441 ("fs: remove no_llseek") To quote that commit, At -rc1 we'll need do a mechanical removal of no_llseek - git grep -l -w no_llseek | grep -v porting.rst | while read i; do sed -i '/\/d' $i done would do it. Unfortunately, that hadn't been done. Linus, could you do that now, so that we could finally put that thing to rest? All instances are of the form .llseek = no_llseek, so it's obviously safe. Signed-off-by: Al Viro Signed-off-by: Linus Torvalds

Merge tag 'auxdisplay-for-v6.11-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k

2024-07-26T18:04:28+00:00

Pull auxdisplay updates from Geert Uytterhoeven: - add support for configuring the boot message on line displays - miscellaneous fixes and improvements * tag 'auxdisplay-for-v6.11-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: auxdisplay: ht16k33: Drop reference after LED registration auxdisplay: Use sizeof(*pointer) instead of sizeof(type) auxdisplay: hd44780: add missing MODULE_DESCRIPTION() macro auxdisplay: linedisp: add missing MODULE_DESCRIPTION() macro auxdisplay: linedisp: Support configuring the boot message auxdisplay: charlcd: Provide a forward declaration

parport: Remove parport_driver.devmodel

2024-07-03T14:44:22+00:00

'devmodel' hasn't actually been used since: 'commit 3275158fa52a ("parport: remove use of devmodel")' and everyone now has it set to true and has been fixed up; remove the flag. (There are still comments all over about it) Signed-off-by: Dr. David Alan Gilbert Acked-by: Sudip Mukherjee Link: https://lore.kernel.org/r/20240502154823.67235-4-linux@treblig.org Signed-off-by: Greg Kroah-Hartman