kernel/linux.git/drivers/usb/gadget/function/f_printer.c, branch v7.2-rc6

usb: gadget: printer: fix infinite loop in printer_read()

2026-07-13T05:10:11+00:00

printer_read() uses the same variable for the requested copy size and the number of bytes actually copied to user space. copy_to_user() returns the number of bytes not copied, so when it fails to copy anything, the computed copied length becomes zero. In that case len, buf, current_rx_bytes and current_rx_buf are left unchanged. If RX data is available and the user buffer remains unwritable, the read loop can repeat indefinitely. Track the copied length separately and return -EFAULT, or the number of bytes already copied, if an iteration makes no progress. Fixes: b185f01a9ab7 ("usb: gadget: printer: factor out f_printer") Cc: stable Reviewed-by: Peter Chen Signed-off-by: Melbin K Mathew Link: https://patch.msgid.link/20260709205622.55700-1-mlbnkm1@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_printer: take kref only for successful open

2026-07-08T11:29:57+00:00

printer_open() returns -EBUSY when the character device is already open, but it increments dev->kref regardless of the return value. VFS does not call ->release() for a failed open, so every rejected second open permanently leaks one reference. Move kref_get() into the successful-open branch. Fixes: e8d5f92b8d30 ("usb: gadget: function: printer: fix use-after-free in __lock_acquire") Cc: stable Signed-off-by: Xu Rao Link: https://patch.msgid.link/80295742B820DA9B+20260626064617.4090626-1-raoxu@uniontech.com Signed-off-by: Greg Kroah-Hartman

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

usb: gadget: Constify struct configfs_item_operations and configfs_group_operations

2025-12-23T14:31:01+00:00

'struct configfs_item_operations' and 'configfs_group_operations' are not modified in these drivers. Constifying these structures moves some data to a read-only section, so increases overall security, especially when the structure holds some function pointers. On a x86_64, with allmodconfig, as an example: Before: ====== text data bss dec hex filename 65061 20968 256 86285 1510d drivers/usb/gadget/configfs.o After: ===== text data bss dec hex filename 66181 19848 256 86285 1510d drivers/usb/gadget/configfs.o Signed-off-by: Christophe JAILLET Link: https://patch.msgid.link/49cec1cb84425f854de80b6d69b53a5a3cda8189.1766164523.git.christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman

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

Merge 6.10-rc6 into usb-next

2024-07-01T11:59:29+00:00

We need the USB fixes in here as well for some follow-on patches. Signed-off-by: Greg Kroah-Hartman

usb: gadget: printer: fix races against disable

2024-06-20T17:33:22+00:00

printer_read() and printer_write() guard against the race against disable() by checking the dev->interface flag, which in turn is guarded by a spinlock. These functions, however, drop the lock on multiple occasions. This means that the test has to be redone after reacquiring the lock and before doing IO. Add the tests. This also addresses CVE-2024-25741 Fixes: 7f2ca14d2f9b9 ("usb: gadget: function: printer: Interface is disabled and returns error") Cc: stable Signed-off-by: Oliver Neukum Link: https://lore.kernel.org/r/20240620114039.5767-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: printer: SS+ support

2024-06-20T17:32:44+00:00

We need to treat super speed plus as super speed, not the default, which is full speed. Signed-off-by: Oliver Neukum Cc: stable Link: https://lore.kernel.org/r/20240620093800.28901-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: add missing MODULE_DESCRIPTION() macros

2024-06-20T17:18:19+00:00

make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/libcomposite.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_acm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ss_lb.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/u_serial.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_serial.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_obex.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/u_ether.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ncm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ecm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_phonet.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_eem.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ecm_subset.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_rndis.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_mass_storage.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_fs.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uac1.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uac1_legacy.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uac2.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uvc.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_midi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_midi2.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_hid.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_printer.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_tcm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/legacy/g_zero.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/legacy/g_midi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/legacy/g_dbgp.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson Link: https://lore.kernel.org/r/20240605-md-drivers-usb-gadget-v1-1-29847a46aad3@quicinc.com Signed-off-by: Greg Kroah-Hartman